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                                                                   EXHIBIT 10.20

                                 SALE AGREEMENT

                                     BETWEEN

                              TRIZEC HOLDINGS, INC.

                             A DELAWARE CORPORATION

                                    AS SELLER

                                       AND

                  BEHRINGER HARVARD OPERATING PARTNERSHIP I LP,
                           A TEXAS LIMITED PARTNERSHIP

                                  AS PURCHASER;


                              AS OF MARCH 29, 2004

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                                                                   EXHIBIT 10.20
                                 SALE AGREEMENT


        THIS SALE AGREEMENT (this "AGREEMENT") is made as of March 29, 2004 (the
"EFFECTIVE DATE"), by and between TRIZEC HOLDINGS, INC. A DELAWARE CORPORATION
("SELLER"), and BEHRINGER HARVARD OPERATING PARTNERSHIP I LP, a Texas limited
partnership ("PURCHASER").


                              W I T N E S S E T H:
                               - - - - - - - - - -

                                ARTICLE(DEGREE)I

                                PURCHASE AND SALE

        1.1     AGREEMENT OF PURCHASE AND SALE. Subject to the terms and
conditions hereinafter set forth, Seller agrees to sell and convey to Purchaser,
and Purchaser agrees to purchase from Seller, the following:

                (a)     those certain tracts or parcels of land situated in St.
        Louis, Missouri, more particularly described in EXHIBIT A attached
        hereto and made a part hereof, together with all rights and
        appurtenances pertaining to such property, including any right, title
        and interest of Seller in and to adjacent streets, alleys or
        rights-of-way (the property described in clause (a) of this Section 1.1
        being herein referred to collectively as the "LAND");

                (b)     office complex commonly known as St. Louis Place (the
        "BUILDING") and all other structures, fixtures and other improvements
        affixed to or located on the Land, excluding fixtures owned by tenants
        (the property described in clause (b) of this Section 1.1 being herein
        referred to collectively as the "IMPROVEMENTS");

                (c)     any and all of Seller's right, title and interest in and
        to all tangible personal property located upon the Land or within the
        Improvements, including, without limitation, any and all appliances,
        furniture, carpeting, draperies and curtains, tools and supplies, and
        other items of personal property owned by Seller (excluding cash,
        computers, any software and the personal property described in EXHIBIT B
        hereto), located on and used exclusively in connection with the
        operation of the Land and the Improvements (the property described in
        clause (c) of this Section 1.1 being herein referred to collectively as
        "PERSONAL PROPERTY");

                (d)     any and all of Seller's right, title and interest in and
        to the leases, licenses and occupancy agreements covering all or any
        portion of the Real Property, to the extent they are in effect on the
        date of the Closing (as such term is defined in Section 4.1 hereof) (the
        property described in clause (d) of this Section 1.1 being herein

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        referred to collectively as the "LEASES"), together with all rents and
        other sums due thereunder for periods from and after the Closing (the
        "RENTS") and any and all refundable security deposits in connection
        therewith (the "SECURITY DEPOSITS"); and

                (e)     any and all of Seller's right, title and interest in and
        to (i) all assignable contracts and agreements (collectively, the
        "OPERATING AGREEMENTS") listed and described on EXHIBIT C attached
        hereto and made a part hereof, relating to the upkeep, repair,
        maintenance or operation of the Land, Improvements or Personal Property,
        and (ii) all assignable existing warranties and guaranties (express or
        implied) issued to Seller in connection with the Improvements or the
        Personal Property, and (iii) all assignable existing permits, licenses,
        approvals and authorizations issued by any governmental authority in
        connection with the Property and (iv) the non-exclusive right to the
        name "ST. LOUIS PLACE", but excluding any right to use the name
        "TRIZEC," "TRIZECHAHN," "TRIZEC PROPERTIES" or any derivation thereof
        (the property described in clause (e) of this Section 1.1 being
        sometimes herein referred to collectively as the "INTANGIBLES").

        1.2     PROPERTY DEFINED. The Land and the Improvements are hereinafter
sometimes referred to collectively as the "REAL PROPERTY." The Land, the
Improvements, the Personal Property, the Leases and the Intangibles are
hereinafter sometimes referred to collectively as the "PROPERTY."

        1.3     PURCHASE PRICE. Seller is to sell and Purchaser is to purchase
the Property for the amount of Thirty Million One Hundred Thousand and No/100
Dollars ($30,100,000.00) (the "PURCHASE PRICE").

        1.4     PAYMENT OF PURCHASE PRICE. The Purchase Price, as increased or
decreased by prorations and adjustments as herein provided, shall be payable in
full at Closing in cash by wire transfer of immediately available funds to a
bank account designated by Seller in writing to Purchaser prior to the Closing.

        1.5     DEPOSIT. Within three (3) business days after the execution and
delivery of this Agreement, Purchaser shall deposit with Partners Title Company
(the "ESCROW AGENT" or the "TITLE COMPANY"), having its office at 712 Main
Street, Suite 2000E, Houston, Texas 77002-3215 (Attention: Karen Highfield) the
sum of One Million and No/100 Dollars ($1,000,000.00) (the "INITIAL DEPOSIT") in
good funds, either by certified bank or cashier's check or by federal wire
transfer. The Initial Deposit, together with any funds deposited with the Escrow
Agent pursuant to Section 4.1, and all interest earned thereon is collectively
called the "DEPOSIT"). The Escrow Agent shall hold the Deposit in an
interest-bearing account reasonably acceptable to Seller and Purchaser, in
accordance with the terms and conditions of this Agreement. All interest on such
sum shall be deemed income of Purchaser, and Purchaser shall be responsible for
the payment of all costs and fees imposed on the Deposit account. The Deposit
shall be delivered to Seller and applied against the Purchase Price at Closing
or otherwise distributed in accordance with the terms of this Agreement. The
failure of Purchaser to timely deliver any Deposit hereunder shall be a material
default, and shall entitle Seller, at Seller's sole option, to exercise the
remedies provided in Section 6.1 hereof, including without

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limitation to receive the Initial Deposit as liquidated damages. Prior to
expiration of the Inspection Period, the escrow established pursuant to the
Agreement shall be deemed to be a "sole order" escrow, and Escrow Agent shall
disburse the Deposit to Purchaser upon Escrow Agent's receipt of any notice of
termination prior to expiration of the Inspection Period, without liability to
Seller and notwithstanding any objection by Seller to such disbursement.

        1.6     ESCROW AGENT. Escrow Agent shall hold and dispose of the Deposit
in accordance with the terms of this Agreement. Seller and Purchaser agree that
the duties of the Escrow Agent hereunder are purely ministerial in nature and
shall be expressly limited to the safekeeping and disposition of the Deposit in
accordance with this Agreement. Escrow Agent shall incur no liability in
connection with the safekeeping or disposition of the Deposit for any reason
other than Escrow Agent's willful misconduct or gross negligence. In the event
that Escrow Agent shall be in doubt as to its duties or obligations with regard
to the Deposit, or in the event that Escrow Agent receives conflicting
instructions from Purchaser and Seller with respect to the Deposit, Escrow Agent
shall not be required to disburse the Deposit and may, at its option, continue
to hold the Deposit until both Purchaser and Seller agree as to its disposition,
or until a final judgment is entered by a court of competent jurisdiction
directing its disposition, or Escrow Agent may interplead the Deposit in
accordance with the laws of the state in which the Property is located.

        Escrow Agent shall not be responsible for any interest on the Deposit
except as is actually earned, or for the loss of any interest resulting from the
withdrawal of the Deposit prior to the date interest is posted thereon.

        Escrow Agent shall execute this Agreement solely for the purpose of
being bound by the provisions of Sections 1.5 and 1.6 hereof.


                                   ARTICLE II

                                TITLE AND SURVEY

        2.1     TITLE REVIEW PERIOD. During the period beginning upon the
Effective Date and ending at 5:00 p.m. (local time at the Property) on April 8,
2004 (hereinafter referred to as the "TITLE REVIEW PERIOD"), Purchaser shall
have the right to review (a) a current preliminary title report on the Real
Property prepared by the Title Company which title report shall be obtained by
Purchaser and provided to Seller within five (5) days after the Effective Date;
and (b) Seller's existing survey of the Real Property (the "SURVEY"), which
Seller has delivered to Purchaser prior to the Effective Date. Purchaser may
obtain an updated survey of the Real Property (the "UPDATED SURVEY"). Purchaser
shall provide a copy of any Updated Survey to Seller upon Purchaser's receipt of
same.

        2.2     TITLE EXAMINATION. Purchaser shall notify Seller in writing (the
"TITLE NOTICE") prior to the expiration of the Title Review Period which
exceptions to title (including

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survey matters), if any, will not be accepted by Purchaser. If Purchaser fails
to notify Seller in writing of its disapproval of any exceptions to title by the
expiration of the Title Review Period, Purchaser shall be deemed to have
approved the condition of title to the Real Property. If Purchaser notifies
Seller in writing that Purchaser objects to any exceptions to title, Seller
shall have three (3) days after receipt of the Title Notice to notify Purchaser
(a) that Seller will remove such objectionable exceptions from title on or
before the Closing; provided that Seller may extend the Closing for such period
as shall be required to effect such cure, but not beyond thirty (30) days; or
(b) that Seller elects not to cause such exceptions to be removed; provided that
Seller shall pay or discharge any monetary liens created, assumed or consented
to by Seller. The procurement by Seller of a commitment for the issuance of the
Title Policy (as defined in Section 4.6 hereof) or an endorsement thereto
insuring Purchaser against any title exception which was disapproved pursuant to
this Section 2.2 shall be deemed a cure by Seller of such disapproval subject to
Purchaser's reasonable approval thereof. If Seller gives Purchaser notice under
clause (b) above, Purchaser shall have until the expiration of the Title Review
Period in which to notify Seller that Purchaser will nevertheless proceed with
the purchase and take title to the Property subject to such exceptions, or that
Purchaser will terminate this Agreement. If Purchaser shall fail to notify
Seller of its election on or before the expiration of the Title Review Period,
Purchaser shall be deemed to have elected to terminate this Agreement. If this
Agreement is terminated or deemed terminated pursuant to the foregoing
provisions of this paragraph, then neither party shall have any further rights
or obligations hereunder (except for those obligations of either party that
expressly survive the termination of this Agreement pursuant to the other
provisions of this Agreement), the Deposit shall be returned to Purchaser and
each party shall bear its own costs incurred hereunder.

        2.3     PRE-CLOSING "GAP" TITLE DEFECTS. Between the expiration of the
Title Review Period and prior to Closing, Purchaser may notify Seller in writing
(the "GAP NOTICE") of any objections to title (a) that did not exist prior to
the expiration of the Title Review Period and are not due to acts done or
suffered by or through Purchaser and (b) are raised by the Title Company between
the expiration of the Title Review Period and the Closing. provided that
Purchaser must notify Seller of such objection to title within two (2) business
days of being made aware of the existence of such exception. If Purchaser sends
a Gap Notice to Seller, Purchaser and Seller shall have the same rights and
obligations with respect to such notice as apply to a Title Notice under Section
2.2 hereof, unless such new matter was created by Seller or with Seller's
consent, in which case, Seller shall satisfy Purchaser's objections relating
thereto at or prior to Closing.

                                   ARTICLE III

                               REVIEW OF PROPERTY

        3.1     RIGHT OF INSPECTION. During the period beginning upon the
Effective Date and ending at 5:00 p.m. (local time at the Property) on April 28,
2004 (hereinafter referred to as the "INSPECTION PERIOD"), Purchaser shall have
the right to make a physical inspection of

<PAGE>

the Real Property, including an inspection of the environmental condition
thereof pursuant to the terms and conditions of this Agreement, and to examine
at the Property (or the property manager's office) all documents and files
concerning the leasing, maintenance and operation of the Property, including
expense budgets and accounting and tax records to the extent related to the
operation of the Property, but excluding Seller's partnership or corporate
records, internal memoranda, operating and revenue budgets, accounting and tax
records, appraisals, financial projections and similar proprietary, confidential
or privileged information (collectively, the "CONFIDENTIAL DOCUMENTS").
Purchaser has advised Seller that Purchaser must cause to be prepared three (3)
years of audited financial statements in respect of the Property in accordance
with the policies of Purchaser and certain laws and regulations including,
without limitation, Securities and Exchange Commission Regulation S-X, 3-14.
Seller agrees to use reasonable efforts to provide to Purchaser such financial
statements and supporting documentation as are necessary for Purchaser's
auditors to prepare such audited financial statements, provided such cooperation
on the part of Seller shall impose no liability on Seller.

        Purchaser understands and agrees that any on-site inspections of the
Property shall occur at reasonable times agreed upon by Seller and Purchaser
after reasonable prior written notice to Seller and shall be conducted so as not
to interfere unreasonably with the use of the Property by Seller or its tenants.
Seller reserves the right to have a representative present during any such
inspections. If Purchaser desires to do any invasive testing at the Property,
Purchaser shall do so only after notifying Seller and obtaining Seller's prior
written consent thereto, which consent may be subject to any terms and
conditions imposed by Seller in its sole discretion. Purchaser shall promptly
restore the Property to its condition prior to any such inspections or tests, at
Purchaser's sole cost and expense. At Seller's option, Purchaser will furnish to
Seller copies of any reports received by Purchaser relating to any inspections
of the Property. Purchaser agrees to protect, indemnify, defend and hold Seller
harmless from and against any claim for liabilities, losses, costs, expenses
(including reasonable attorneys' fees), damages or injuries arising out of or
resulting from the inspection of the Property by Purchaser or its agents or
consultants (excluding discovery of condition), and notwithstanding anything to
the contrary in this Agreement, such obligation to indemnify and hold harmless
Seller shall survive Closing or any termination of this Agreement. Unless
legally required to report a condition that is revealed by inspections,
Purchaser shall not contact any governmental authority without first obtaining
the prior written consent of Seller thereto and Seller, at Seller's election,
shall be entitled to have a representative on any telephone call or other
contact made by Purchaser to a governmental authority and to be present at any
meeting between Purchaser and a governmental authority. The foregoing shall not,
however, prevent Purchaser from contacting governmental authorities to request
zoning and code compliance letters for customary due diligence and shall not
prohibit Purchaser from reviewing or requesting copies of public files relating
to the Property. Purchaser shall maintain and shall assure that its contractors
maintain public liability and property damage insurance in amounts and in form
and substance adequate to insure against all liabilities of Purchaser and its
agents, employees or contractors arising out of any entry upon or inspection of
the Property pursuant to the provisions hereof and concurrently with the
execution hereof, Purchaser shall provide Seller with evidence of such insurance
coverage naming Seller as an additional insured party thereunder.

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        3.2     REPORTS. PURCHASER ACKNOWLEDGES THAT (1) PURCHASER HAS RECEIVED
COPIES OF THE ENVIRONMENTAL, ENGINEERING AND OTHER REPORTS (COLLECTIVELY, THE
"REPORTS") LISTED ON EXHIBIT P ATTACHED HERETO, (2) IF SELLER DELIVERS ANY
ADDITIONAL REPORTS TO PURCHASER, PURCHASER WILL ACKNOWLEDGE IN WRITING THAT IT
HAS RECEIVED SUCH REPORTS PROMPTLY UPON RECEIPT THEREOF, AND (3) ANY REPORTS
DELIVERED OR TO BE DELIVERED BY SELLER OR ITS AGENTS OR CONSULTANTS TO PURCHASER
ARE BEING MADE AVAILABLE SOLELY AS AN ACCOMMODATION TO PURCHASER AND MAY NOT BE
RELIED UPON BY PURCHASER IN CONNECTION WITH THE PURCHASE OF THE PROPERTY.
PURCHASER AGREES THAT SELLER SHALL HAVE NO LIABILITY OR OBLIGATION WHATSOEVER
FOR ANY INACCURACY IN OR OMISSION FROM ANY REPORT. PURCHASER HAS CONDUCTED, OR
WILL CONDUCT PRIOR TO THE EXPIRATION OF THE INSPECTION PERIOD, ITS OWN
INVESTIGATION OF THE CONDITION OF THE PROPERTY TO THE EXTENT PURCHASER DEEMS
SUCH AN INVESTIGATION TO BE NECESSARY OR APPROPRIATE.

        3.3     RIGHT OF TERMINATION. If for any reason whatsoever Purchaser
determines that the Property or any aspect thereof is unsuitable for Purchaser's
acquisition, Purchaser shall have the right to terminate this Agreement, in its
sole discretion and for any reason or no reason by giving written notice thereof
to Seller prior to the expiration of the period beginning upon the Effective
Date and ending at 5:00 p.m. (local time at the Property) on April 15, 2004
(hereinafter referred to as the "INITIAL REVIEW PERIOD"), and if Purchaser gives
such notice of termination within the Initial Review Period, this Agreement
shall terminate. In addition, if Purchaser determines that the Property is
unsuitable for Purchaser's acquisition based solely on material information (the
"PHYSICAL OR ENVIRONMENTAL DATA") about the physical condition of the Property
(including the environmental condition thereof) discovered by Purchaser during
Purchaser's physical inspection of the Property, Purchaser shall have the right
to terminate this Agreement by giving written notice thereof to Seller prior to
the expiration of the Inspection Period together with a copy of the pertinent
portions of the physical or environmental reports on which Seller is basing its
decision to terminate. If this Agreement is terminated pursuant to either of the
foregoing provisions of this paragraph, then neither party shall have any
further rights or obligations hereunder (except for those obligations that
expressly survive the termination of this Agreement), the Deposit shall be
returned to Purchaser and each party shall bear its own costs incurred
hereunder. If Purchaser fails to give Seller a notice of termination prior to
the expiration of the Initial Review Period or the Inspection Period, Purchaser
shall be deemed to have approved all aspects of the Property (except title and
survey, which shall be governed by Article II hereof) and to have elected to
proceed with the purchase of the Property pursuant to the terms hereof, subject
to all conditions to Closing otherwise specified herein.

        3.4     REVIEW OF TENANT ESTOPPELS. Promptly following the expiration of
the Inspection Period, Seller shall deliver to each tenant of the Property an
estoppel certificate in substantially the form of EXHIBIT D attached hereto
(each, an "ESTOPPEL CERTIFICATE"), and shall

<PAGE>

request that the tenants complete and sign the Estoppel Certificates and return
them to Seller. Seller shall deliver copies of the completed Estoppel
Certificates to Purchaser as Seller receives them.

        3.5     SUBORDINATION, NON-DISTURBANCE AND ATTORNMENT AGREEMENTS. Seller
agrees to cooperate with Purchaser to obtain subordination, non-disturbance and
attornment agreements ("SNDAS") from tenants under Leases selected by
Purchaser's lender. As and when received by Seller, Seller shall deliver the
executed SNDAs to Purchaser. If the transaction contemplated herein fails to
close for any reason whatsoever, Purchaser shall return to Seller all such
executed SNDAs previously delivered to Purchaser. The failure to obtain SNDAs
from all or any of the selected tenants shall not constitute a default by Seller
hereunder or otherwise entitle Purchaser to terminate this Agreement.

        3.6     MOSER & MARSALEK LEASE. Seller and Purchaser acknowledge and
agree that Seller and Moser & Marsalek ("M&M"), a current tenant of the
Building, are in negotiations to renew or extend the term of M&M's existing
lease in the Building on the terms contained in the letter of intent attached
hereto as SCHEDULE 1 and made a part hereof (the "M&M EXTENSION LEASE"). If
Seller has not provided Purchaser with an executed copy of the M&M Extension
Lease on or prior to April 21, 2004, then Purchaser may terminate this Agreement
by giving a written notice to Seller before the expiration of the Inspection
Period, in which event the Deposit shall be returned to Purchaser and neither
party shall have any further rights or obligations hereunder (except for those
that expressly survive the termination of this Agreement). If Purchaser fails to
give Seller a notice of termination prior to the expiration of the Inspection
Period, Purchaser shall be deemed to have elected to proceed with the purchase
of the Property without the M&M Extension Lease being in place, pursuant to the
terms hereof, subject to all conditions to Closing otherwise specified herein.

        3.7     MANAGEMENT AGREEMENT. Seller and Purchaser hereby acknowledge
and agree that they are in the process of negotiating the leasing commissions
("COMMISSIONS") to be attached as Exhibit B to the Management Agreement (as
hereinafter defined) and the pro forma leasing projections ("PROJECTIONS") to be
attached as Exhibit E to the Management Agreement. Seller and Purchaser hereby
agree that during the Inspection Period they will work in good faith to agree
upon mutually acceptable Commissions and Projections and if Seller and Purchaser
are unable to do so, then either Seller or Purchaser shall have the right to
terminate this agreement by delivering a written termination notice to the other
on or before the expiration of the Inspection Period, in which event the Deposit
shall be returned to Purchaser and neither party shall have any further rights
or obligations hereunder (except for those that expressly survive the
termination of this Agreement).

                                   ARTICLE IV

                                     CLOSING

        4.1     TIME AND PLACE. The consummation of the transaction contemplated
hereby (the "CLOSING") shall be held at the Chicago offices of Piper Rudnick on
May 13, 2004

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(the "CLOSING DATE"). At the Closing, Seller and Purchaser shall perform the
obligations set forth in, respectively, Section 4.2 and Section 4.3 hereof, the
performance of which obligations shall be concurrent conditions. At Seller's
option, the Closing shall be consummated through an escrow administered by
Escrow Agent. In such event, the Purchase Price and all documents shall be
deposited with the Escrow Agent, as escrowee. Notwithstanding the foregoing, by
delivering, at least three (3) business days prior to the original Closing Date,
(a) to Seller a written notice ("EXTENSION NOTICE") and (b) to Escrow Agent
(concurrently with the delivery of a copy of the Extension Notice) by wire
transfer immediately available funds in the amount of One Million and No/100
Dollars ($1,000,000.00) to be held by Escrow Agent as an addition to the
Deposit, Purchaser may elect to extend the Closing Date to a date no later than
May 28, 2004, which extended Closing Date shall be specified in the Extension
Notice.

        4.2     SELLER'S OBLIGATIONS AT CLOSING. At Closing, Seller shall:

                (a)     deliver to Purchaser a duly executed special warranty
        deed (the "DEED") in the form attached hereto as EXHIBIT E, conveying
        the Land and Improvements, subject only to the Permitted Exceptions (as
        hereinafter defined); the warranty of title in the Deed will be only as
        to claims made by, through or under Seller and not otherwise;

                (b)     deliver to Purchaser a duly executed bill of sale
        (collectively, the "BILL OF SALE") conveying the Personal Property
        without warranty of title or use and without warranty, express or
        implied, as to, merchantability and fitness for any purpose and in the
        form attached hereto as EXHIBIT F;

                (c)     assign to Purchaser, and Purchaser shall assume, the
        landlord/lessor interest in and to the Leases, Rents and Security
        Deposits, and any and all obligations to pay Commissions and finder's
        fees with respect to the Leases and amendments, renewals and expansions
        thereof, to the extent provided in Section 4.4(b)(v) hereof, by duly
        executed assignment and assumption agreements (collectively, the
        "ASSIGNMENT OF LEASES") in the form attached hereto as EXHIBIT G;

                (d)     to the extent assignable, assign to Purchaser, and
        Purchaser shall assume, Seller's interest in the Operating Agreements
        and the other Intangibles by duly executed assignment and assumption
        agreements (collectively, the "ASSIGNMENT OF CONTRACTS") in the form
        attached hereto as EXHIBIT H;

                (e)     join with Purchaser to execute a notice (the "TENANT
        NOTICE") in the form attached hereto as EXHIBIT I, which Purchaser shall
        send to each tenant under each of the Leases promptly after the Closing,
        informing such tenant of the sale of the Property and of the assignment
        to Purchaser of Seller's interest in, and obligations under, the Leases
        (including, if applicable, any Security Deposits), and directing that
        all Rent and other sums payable after the Closing under each such Lease
        be paid as set forth in the notice;

<PAGE>

                (f)     deliver to Purchaser the Seller Representation
        Certificate (as defined in Section 4.6(b) hereof). In no event shall
        Seller be liable to Purchaser for, or be deemed to be in default
        hereunder by reason of, any breach of representation or warranty which
        results from any change that (i) occurs between the Effective Date and
        the Closing Date and (ii) is expressly permitted under the terms of this
        Agreement or is beyond the reasonable control of Seller to prevent;

                (g)     deliver to Purchaser such evidence as the Title Company
        may reasonably require as to the authority of the person or persons
        executing documents on behalf of Seller;

                (h)     deliver to Purchaser certificates in the form attached
        hereto as EXHIBIT J duly executed by Seller stating that Seller is not a
        "foreign person" as defined in the Federal Foreign Investment in Real
        Property Tax Act of 1980;

                (i)     deliver to Purchaser the Leases and the Operating
        Agreements, together with such leasing and property files and records
        which are material in connection with the continued operation, leasing
        and maintenance of the Property, but excluding any Confidential
        Documents;

                (j)     deliver such affidavits as may be customarily and
        reasonably required by the Title Company, in a form reasonably
        acceptable to Seller;

                (k)     deliver to Purchaser possession and occupancy of the
        Property, subject to the Permitted Exceptions;

                (l)     execute a closing and proration statement;

                (m)     execute and deliver to Purchaser a lease (the "TRIZEC
        LEASE") in the form attached hereto as EXHIBIT Q.

                (n)     cause an affiliate of Seller ("TRIZEC MANAGER") to
        execute and deliver the Management Agreement in the form attached hereto
        as EXHIBIT R; and

                (o)     deliver such additional documents as shall be reasonably
        required to consummate the transaction contemplated by this Agreement.

        4.3     PURCHASER'S OBLIGATIONS AT CLOSING. At Closing, Purchaser shall:

                (a)     pay to Seller the full amount of the Purchase Price
        (which amount shall include the Deposit), as increased or decreased by
        prorations and adjustments as herein provided, in immediately available
        wire transferred funds pursuant to Section 1.4 hereof;

                (b)     join Seller in execution of the Assignment of Leases,
        Assignment of Contracts, Tenant Notices and the Trizec Lease;

<PAGE>

                (c)     in the event that any representation or warranty of
        Purchaser set forth in Sections 5.7(a) or (b) hereof needs to be
        modified due to changes since the Effective Date, deliver to Seller a
        certificate, dated as of the Closing Date and executed on behalf of
        Purchaser by a duly authorized representative thereof, identifying any
        such representation or warranty which is no longer true and correct and
        explaining the state of facts giving rise to the change. In no event
        shall Purchaser be liable to Seller for, or be deemed to be in default
        hereunder by reason of, any breach of representation or warranty set
        forth in Sections 5.7(a) or (b) hereof which results from any change
        that (i) occurs between the Effective Date and the Closing Date and (ii)
        is expressly permitted under the terms of this Agreement or is beyond
        the reasonable control of Purchaser to prevent;

                (d)     deliver to Seller such evidence as the Title Company may
        reasonably require as to the authority of the person or persons
        executing documents on behalf of Purchaser;

                (e)     deliver such affidavits as may be customarily and
        reasonably required by the Title Company, in a form reasonably
        acceptable to Purchaser;

                (f)     execute a closing and proration statement;

                (g)     execute and deliver the Management Agreement to Trizec
        Manager; and

                (h)     deliver such additional documents as shall be reasonably
        required to consummate the transaction contemplated by this Agreement.

        4.4     CREDITS AND PRORATIONS.

                (a)     Seller shall endeavor to provide Purchaser with a draft
        of the closing and proration statement referred to in Sections 4.2(l)
        and 4.3(l) (the "CLOSING STATEMENT") on or before the date that is five
        (5) business days prior to the Closing Date. If Seller fails to deliver
        such draft Closing Statement on or before such date, such failure shall
        not constitute a default by Seller hereunder or otherwise entitle
        Purchaser to terminate this Agreement.

                (b)     All income and expenses of the Property shall be
        apportioned as of 12:01 a.m., on the Closing Date, as if Purchaser were
        vested with title to the Property during the entire day upon which
        Closing occurs. Such prorated items shall include without limitation the
        following:

                        (i)     all Rents;

                        (ii)    taxes and assessments (including personal
                property taxes on the Personal Property) levied against the
                Property;

<PAGE>

                        (iii)   utility charges for which Seller is liable, if
                any, such charges to be apportioned at Closing on the basis of
                the most recent meter reading occurring prior to Closing (dated
                not more than fifteen (15) days prior to Closing) or, if
                unmetered, on the basis of a current bill for each such utility;

                        (iv)    all amounts payable under Operating Agreements;
                and

                        (v)     any other operating expenses or other items
                pertaining to the Property which are customarily prorated
                between a purchaser and a seller in the county in which the
                Property is located.

                (c)     In addition to and notwithstanding anything contained in
        Section 4.4(b) hereof:

                        (i)     At Closing, (A) Seller shall, at Seller's
                option, either deliver to Purchaser any Security Deposits
                provided under the Leases or credit to the account of Purchaser
                the amount of such Security Deposits (to the extent such
                Security Deposits have not been applied against delinquent Rents
                or otherwise as provided in the Leases, any amounts so supplied
                being disclosed to Purchaser in writing with a representation by
                Seller that the tenant who posted such applied Security Deposit
                is not entitled to a refund of the applied amount), and (B)
                Purchaser shall credit to the account of Seller all refundable
                cash or other deposits posted with utility companies serving the
                Property to the extent transferred to Seller on the utility
                company's records, or, at Seller's option, Seller shall be
                entitled to receive and retain such refundable cash and
                deposits;

                        (ii)    Any taxes paid at or prior to Closing shall be
                prorated based upon the amounts actually paid. If taxes and
                assessments due and payable during the year of Closing have not
                been paid before Closing, Seller shall be charged at Closing an
                amount equal to that portion of such taxes and assessments which
                relates to the period before Closing and Purchaser shall pay the
                taxes and assessments prior to their becoming delinquent and on
                or prior to the date that will maximize any discounts or
                reductions in said taxes and assessments on account of early
                payment thereof. Any such apportionment made with respect to a
                tax year for which the tax rate or assessed valuation, or both,
                have not yet been fixed shall be based upon the tax rate and/or
                assessed valuation last fixed. To the extent that the actual
                taxes and assessments for the current year differ from the
                amount apportioned at Closing, the parties shall make all
                necessary adjustments by appropriate payments between themselves
                within thirty (30) days after such amounts are determined
                following Closing, subject to the provisions of Section 4.4(e)
                hereof;

                        (iii)   Non-delinquent charges referred to in Section
                4.4(b) hereof which are payable by any tenant to a third party
                shall not be apportioned hereunder, and Purchaser shall accept
                title subject to any of such charges unpaid

<PAGE>

                and Purchaser shall look solely to the tenant responsible
                therefor for the payment of the same. If Seller shall have paid
                any of such charges on behalf of any tenant, and shall not have
                been reimbursed therefor by the time of Closing, Purchaser shall
                deliver the reimbursement due Seller upon receipt of the same
                from the tenant(s) who are responsible for payment;

                        (iv)    As to utility charges referred to in Section
                4.4(a)(iii) hereof, Seller may on notice to Purchaser elect to
                pay one or more of all of said items accrued to the date
                hereinabove fixed for apportionment directly to the person or
                entity entitled thereto, and to the extent Seller so elects,
                such item shall not be apportioned hereunder, and Seller's
                obligation to pay such item directly in such case shall survive
                the Closing or any termination of this Agreement;

                        (v)     Purchaser shall be responsible for the payment
                of (A) all Tenant Inducement Costs (as hereinafter defined) and
                Commissions (as hereinafter defined) which become due and
                payable (whether before or after Closing) as a result of any new
                Leases, or any renewals, amendments or expansions of existing
                Leases, signed during the Lease Approval Period (as hereinafter
                defined) or as a result of any options exercised by tenants
                during the Lease Approval Period, including, without limitation,
                the Commissions and Tenant Inducement Costs set forth on
                SCHEDULE 2, attached hereto and made a part hereof and any
                Commissions or Tenant Inducement Costs (up to a maximum of
                $35.00 per rentable square foot) payable in connection with M&M
                Extension Lease (as defined in Section 4.6(f)) and, if required,
                approved or deemed approved in accordance with Section 5.6
                hereof; and (B) all Tenant Inducement Costs and Commissions as a
                result of new leases, or renewals, amendments or expansions of
                existing Leases, signed or entered into from and after the
                Closing Date or as a result of any options exercised by tenants
                after the Closing Date. If, as of the Closing Date, Seller shall
                have paid any Tenant Inducement Costs or Commissions for which
                Purchaser is responsible pursuant to the foregoing provisions,
                Purchaser shall reimburse Seller therefor at Closing. As used
                herein (a) "COMMISSIONS" shall mean all brokerage commissions,
                finder's fees or other similar compensation due or payable in
                connection with the applicable lease and (b) "TENANT INDUCEMENT
                COSTS" shall mean any out-of-pocket payments required under a
                Lease to be paid by the landlord thereunder to or for the
                benefit of the tenant thereunder which is in the nature of a
                tenant inducement, including specifically, without limitation,
                tenant improvement costs, lease buyout costs, and moving,
                design, refurbishment and club membership allowances. The term
                "Tenant Inducement Costs" shall not include loss of income
                resulting from any free rental period, it being agreed that
                Seller shall bear the loss resulting from any free rental period
                until the Closing Date and that Purchaser shall bear such loss
                from and after the Closing Date. For purposes hereof, the term
                "LEASE APPROVAL PERIOD" shall mean the period from the Effective
                Date until the Closing Date;

<PAGE>

                        (vi)    (x) Seller shall be responsible for determining
                the actual amount of Reimbursable Tenant Expenses (as
                hereinafter defined) for the calendar year of 2003 (the "ACTUAL
                2003 EXPENSES"). As used herein, the term "REIMBURSABLE TENANT
                EXPENSES" shall mean payments required to be paid by tenants
                under Leases for such tenant's share of ad valorem taxes,
                insurance, common area maintenance and/or other operating
                expenses of the Property. Within one hundred twenty (120) days
                following Closing, Seller shall provide Purchaser with evidence
                of the Actual 2003 Expenses in a form reasonably satisfactory to
                Purchaser. If the Actual 2003 Expenses reflect an underpayment
                of Reimbursable Tenant Expenses by tenants, then Purchaser shall
                use reasonable efforts to collect from the tenants of the
                Property any such underpayment and pay to Seller said
                underpayment promptly upon collection thereof. If the Actual
                2003 Expenses reflect an overpayment of Reimbursable Tenant
                Expenses by tenants, Seller shall refund Purchaser the amount of
                such overpayment to the extent that such overpayments have not
                previously been refunded to tenants or credited to Purchaser at
                Closing. Purchaser shall be responsible for determining the
                actual amount of Reimbursable Tenant Expenses for the year in
                which the Closing occurs. Purchaser shall use reasonable efforts
                to collect from the tenants of the Property any underpayment of
                Reimbursable Tenant Expenses for the year in which the Closing
                occurs and to pay to Seller Seller's share of said underpayment
                promptly upon collection thereof. Likewise any overpayments
                shall similarly be adjusted and Seller shall refund Purchaser
                its prorata share of such overpayments to the extent such
                overpayments have not previously been refunded to tenants or
                credited to Purchaser at Closing;

                        (vii)   Unpaid and delinquent Rent collected by Seller
                and Purchaser after the Closing Date shall be delivered as
                follows: (a) if Seller collects any unpaid or delinquent Rent
                for the Property, Seller shall, within fifteen (15) days after
                the receipt thereof, deliver to Purchaser any such Rent which
                Purchaser is entitled to hereunder relating to the Closing Date
                and any period thereafter, and (b) if Purchaser collects any
                unpaid or delinquent Rent from the Property, Purchaser shall,
                within fifteen (15) days after the receipt thereof, deliver to
                Seller any such Rent which Seller is entitled to hereunder
                relating to the period prior to the Closing Date. Seller and
                Purchaser agree that (i) all Rent received by Seller or
                Purchaser within the first ninety (90) day period after the
                Closing Date shall be applied first to reasonable costs of
                collection, then to current Rent, and then to delinquent Rent,
                if any, in the inverse order of their maturity. Purchaser will
                make a good faith effort after Closing to collect all Rents in
                the usual course of Purchaser's operation of the Property, but
                Purchaser will not be obligated to institute any lawsuit or
                other collection procedures to collect delinquent Rents. Seller
                may attempt to collect any delinquent Rents owed Seller and may
                institute any lawsuit or collection procedures, but may not
                evict any tenant. In the event that there shall be any Rents or
                other charges under any Leases which, although relating to a
                period prior to Closing, do not become due and payable until
                after Closing or are paid prior to Closing but are subject to
                adjustment after Closing

<PAGE>

                (such as Reimbursable Tenant Expenses), then any Rents or
                charges of such type received by Purchaser or its agents or
                Seller or its agents subsequent to Closing shall, to the extent
                applicable to a period extending through the Closing, be
                prorated between Seller and Purchaser as of Closing, with each
                party promptly remitting to the other amounts due as a result of
                such proration.

                (d)     For a period of three (3) years after the Closing and
        upon reasonable advance written notice, Purchaser shall allow Seller and
        its agents and representatives access without charge to all files,
        records and documents delivered to Purchaser at the Closing, upon
        reasonable advance notice and at all reasonable times, to examine and,
        at Seller's expense make copies of any and all such files, records and
        documents, which right shall survive the Closing;

                (e)     Except as otherwise provided herein, any revenue or
        expense amount which cannot be ascertained with certainty as of Closing
        shall be prorated on the basis of the parties' reasonable estimates of
        such amount, and shall be the subject of a final proration thirty (30)
        days after Closing, or as soon thereafter as the precise amounts can be
        ascertained; but in no event shall any reproration under this Agreement,
        other than with respect to taxes and assessments pursuant to Section
        4.4(b)(ii) above and Reimbursable Tenant Expenses pursuant to Section
        4.4(b)(vi) above, occur more than 180 days after the Closing. Purchaser
        shall promptly notify Seller when it becomes aware that any such
        estimated amount has been ascertained. Once all revenue and expense
        amounts have been ascertained, Purchaser shall prepare, and certify as
        correct, a final proration statement which shall be subject to Seller's
        approval. Upon Seller's acceptance and approval of any final proration
        statement submitted by Purchaser, such statement shall be conclusively
        deemed to be accurate and final.

                (f)     Subject to Section 4.4(e) hereof, the provisions of this
        Section 4.4 shall survive Closing.

        4.5     TRANSACTION TAXES AND CLOSING COSTS.

                (a)     Seller and Purchaser shall execute such returns,
        questionnaires and other documents as shall be required with regard to
        all applicable real property transaction taxes imposed by applicable
        federal, state or local law or ordinance;

                (b)     Seller shall pay the fees of any counsel representing
        Seller in connection with this transaction. Seller shall also pay the
        following costs and expenses: (i) one-half (1/2) escrow fee, if any,
        which may be charged by the Escrow Agent or Title Company; (ii) the cost
        of paying off Seller's existing financing and obtaining applicable
        releases, including but not limited to payment of any prepayment premium
        or defeasance costs; and (iii) the cost of the Updated Survey.

                (c)     Purchaser shall pay the fees of any counsel representing
        Purchaser in connection with this transaction. Purchaser shall also pay
        the following costs and

<PAGE>

        expenses: (i) one half (1/2) of the escrow fee, if any, which may be
        charged by the Escrow Agent or Title Companies; (ii) the premium for the
        Title Policy to be issued to Purchaser by the Title Company at Closing,
        including any endorsements to the Title Policy; (iii) all costs and
        expenses incurred in connection with the transfer of any transferable
        permits, warranties, licenses or non-cash security deposits in
        connection with the ownership or operation of the Property; (v) fees for
        recording the deed and any transfer tax, sales tax, documentary stamp
        tax or similar tax which becomes payable by reason of the transfer of
        the Property, and (vi) all costs and expenses associated with
        Purchaser's financing.

                (d)     The Personal Property is included in this sale without
        charge, and Seller shall pay the amount of any and all sales or similar
        taxes payable in connection with the transfer of the Personal Property.
        Purchaser and Seller shall execute and deliver any tax returns required
        in connection therewith;

                (e)     All costs and expenses incident to this transaction and
        the closing thereof, and not specifically described above, shall be paid
        by the party incurring same; and

                (f)     The provisions of this Section 4.5 shall survive the
        Closing.

        4.6     CONDITIONS PRECEDENT TO OBLIGATION OF PURCHASER. The obligation
of Purchaser to consummate the transaction hereunder shall be subject to the
fulfillment on or before the Closing Date of all of the following conditions,
any or all of which may be waived by Purchaser in its sole discretion:

                (a)     Seller shall have delivered to Purchaser all of the
        items required to be delivered to Purchaser pursuant to the terms of
        this Agreement, including but not limited to, those provided for in
        Section 4.2 hereof;

                (b)     All of the representations and warranties of Seller
        contained in this Agreement shall be true and correct when made and as
        of the Closing Date and, at Closing, Seller shall deliver to Purchaser a
        certificate to that effect (the "SELLER REPRESENTATION CERTIFICATE").
        Notwithstanding the foregoing, unless the Seller Representation
        Certificate discloses the existence of a Material Adverse Effect (as
        defined in Section 4.6(g) hereof), the condition set forth in this
        Section 4.6(b) shall be deemed to be satisfied;

                (c)     Seller shall have performed and observed in all material
        respects all covenants and agreements of this Agreement to be performed
        and observed by Seller as of the Closing Date;

                (d)     The Property shall be conveyed at Closing subject only
        to the following matters, which are hereinafter referred to as the
        "PERMITTED EXCEPTIONS":

<PAGE>

                        (i)     those matters that either are not objected to in
                writing within the time periods provided in Sections 2.2 or 2.3
                hereof, or if objected to in writing by Purchaser, are those
                which Seller has elected not to remove or cure, or has been
                unable to remove or cure, and subject to which Purchaser has
                elected or is deemed to have elected to accept the conveyance of
                the Property;

                        (ii)    the rights of tenants under the Leases;

                        (iii)   the lien of all ad valorem real estate taxes and
                assessments not yet due and payable as of the Closing Date (as
                defined in Section 4.1), subject to adjustment as herein
                provided;

                        (iv)    local, state and federal laws, ordinances or
                governmental regulations, including but not limited to, building
                and zoning laws, ordinances and regulations, now or hereafter in
                effect relating to the Property; and

                        (v)     matters that have arisen as a result of acts
                done or suffered by or through Purchaser.

        Evidence of delivery of title subject only to the Permitted Exceptions
shall be the issuance by the Title Company, and/or another national title
company of its Owner's Policy of Title Insurance (the "TITLE POLICY") covering
the Real Property, in the aggregate amount of the Purchase Price, subject only
to the Permitted Exceptions.

                (e)     No later than five (5) days prior to Closing, Purchaser
        shall have received, from tenants leasing eighty-five percent (85%) or
        more of the leased area of the Building (specifically including, in any
        event, all tenants who lease more than 10,000 rentable square feet in
        the Building) Estoppel Certificates addressed to Purchaser and any other
        person designated by Purchaser, dated not earlier than the first day
        after the expiration of the Inspection Period, substantially in the form
        of EXHIBIT D. Purchaser agrees that an Estoppel Certificate shall be
        deemed to satisfy the requirements of this Section 4.6(e) even though it
        may not be in the form or substance of EXHIBIT D, provided that the
        Estoppel Certificate (i) states that no material defaults have occurred
        under the lease and confirms the economic terms of the lease, or (ii)
        contains the specific information (as opposed to a general or "catch
        all" requirement), if any, required by the applicable lease, or (iii)
        does not depart from the form of Estoppel Certificate attached as
        EXHIBIT D other than to reflect facts or circumstances that are
        disclosed in writing by Seller or that were known to Purchaser through
        its inspection of the Property prior to the expiration of the Inspection
        Period.

                (f)     No event(s) shall have occurred or condition arisen,
        after the Effective Date with respect to the Property (other than any
        loss or damage to the Property caused by fire or other casualty or
        condemnation which shall be governed by the terms of Article VII
        hereof), the result(s) of which may reasonably be expected to have an
        adverse effect on the value of the Property (in the aggregate) which
        would in the reasonable opinion of an investment sales broker reasonably
        selected by Purchaser and Seller be

<PAGE>

        equal to or greater than Two Hundred Fifty Thousand and No/100 Dollars
        ($250,000.00) (a "MATERIAL ADVERSE EFFECT").

        If any of the conditions to Purchaser's obligations under Section 4.6
shall fail to occur and such failure is not otherwise a default under this
Agreement (in which event Purchaser would be afforded the rights under Section
6.2 hereof), then Purchaser may, as long as Purchaser is not in default
hereunder, and as its sole and exclusive remedy, terminate this Agreement by
written notice to Seller, in which event the Deposit shall be promptly returned
to Purchaser and neither party shall have any further rights or obligations
hereunder (except for those obligations of either party that expressly survive
the termination of this Agreement pursuant to the other provisions of this
Agreement). Notwithstanding the foregoing, in the event any condition to
Purchaser's obligations hereunder described in this Section 4.6 shall not have
been satisfied, Seller may elect by notice to Purchaser to extend the Closing
for a period not to exceed thirty (30) days in order to satisfy such condition.

        4.7     CONDITIONS PRECEDENT TO OBLIGATION OF SELLER. The obligation of
Seller to consummate the transaction hereunder shall be subject to the
fulfillment on or before the Closing Date of all of the following conditions,
any or all of which may be waived by Seller in its sole discretion:

                (a)     Seller shall have received the Purchase Price as
        adjusted as provided herein, pursuant to and payable in the manner
        provided for in this Agreement;

                (b)     Purchaser shall have delivered to Seller all of the
        items required to be delivered to Seller pursuant to the terms of this
        Agreement, including but not limited to, those provided for in Section
        4.3 hereof;

                (c)     All of the representations and warranties of Purchaser
        contained in this Agreement shall be true and correct in all material
        respects as of the Closing Date (with appropriate modifications
        permitted under this Agreement); and

                (d)     Purchaser shall have performed and observed in all
        material respects all covenants and agreements of this Agreement to be
        performed and observed by Purchaser as of the Closing Date.

                                    ARTICLE V

                    REPRESENTATIONS, WARRANTIES AND COVENANTS

        5.1     REPRESENTATIONS AND WARRANTIES OF SELLER. Seller hereby makes
the following representations and warranties to Purchaser as of the Effective
Date, which representations and warranties shall be deemed to have been made
again as of the Closing, subject to Section 4.2(f) hereof:

<PAGE>

                (a)     ORGANIZATION AND AUTHORITY. Seller has been duly
        organized and is validly existing under the laws of the State of
        Delaware. Seller has the full right and authority to enter into this
        Agreement and to transfer all of the Property and to consummate or cause
        to be consummated the transaction contemplated by this Agreement. The
        person signing this Agreement on behalf of Seller is authorized to do
        so.

                (b)     OPERATING AGREEMENTS. The Operating Agreements listed on
        EXHIBIT C are all of the agreements concerning the operation and
        maintenance of the Property entered into by or on behalf of Seller and
        affecting the Property and Seller has no knowledge of any other
        Operating Agreements that would be binding on Purchaser or the Property
        after Closing, except those operating agreements that are to be
        terminated by Seller within thirty (30) days after the Closing, and
        except any agreement with Seller's property manager, which shall be
        terminated by Seller as of the Closing Date.

                (c)     LEASE BROKERAGE. There are no agreements with brokers
        providing for the payment by Seller or to, Seller's knowledge, Seller's
        predecessors-in-interest under the Leases, of Commissions or fees for
        procuring tenants with respect to any lease in effect on the date hereof
        (the "EXISTING LEASES"), except as disclosed in EXHIBIT K hereto; and to
        Seller's knowledge, no commission, fee or other compensation is payable
        (or will, with the passage of time or occurrence of any event or both,
        be payable), with respect to the current term of the Existing Leases
        except as disclosed in EXHIBIT K. Seller has not agreed in writing to
        pay and, to Seller's knowledge, there are no Commissions, fees or other
        compensation payable in respect of the exercise of renewal, extension or
        expansion options set forth in the Existing Leases except as disclosed
        in EXHIBIT K.

                (d)     CONDEMNATION. Seller has neither received written notice
        of any pending or threatened condemnation or eminent domain proceedings
        relating to or affecting the Property and Seller has no knowledge of the
        same.

                (e)     LITIGATION. To Seller's knowledge, except as set forth
        on EXHIBIT L attached hereto, there is no litigation which has been
        filed or threatened against Seller that arises out of the ownership or
        operation of the Property;

                (f)     VIOLATIONS. To Seller's knowledge, except as set forth
        on EXHIBIT M attached hereto, Seller has not received notice of any
        uncured violation of any Legal Requirements relating to the use or
        operation of the Property which would materially adversely affect the
        Property or use thereof; and

                (g)     LEASES. The list of Existing Leases attached hereto as
        EXHIBIT N is accurate in all material respects. There are no Leases or
        other tenancies for any space in the Real Property other than those set
        forth on EXHIBIT N. Except as otherwise disclosed on EXHIBIT O or
        elsewhere in this Agreement; Seller has not received from any tenant
        under a Lease a written notice of default by Seller as landlord under
        such Lease or a written notice of violation of any Legal Requirements,
        and to Seller's knowledge, Seller

<PAGE>

        is not in default as landlord under any of the Leases which would give
        rise to the right of termination of any Lease in favor of a tenant.
        Except as set forth on EXHIBIT O, Seller has not sent any tenant under a
        Lease a written notice of default by the tenant under such Lease, and to
        Seller's knowledge, no tenant is in default under any of the Leases,
        which would give rise to the right of termination of any lease in favor
        of the landlord under the Leases if such default is not cured within any
        applicable grace, notice or cure period.

                (h)     NAME. To Seller's knowledge, without investigation,
        Seller has received no written notice of a claim of infringement of
        intellectual property rights arising out of Seller's use of the name
        "St. Louis Place" in connection with the Property.

        5.2     KNOWLEDGE DEFINED. References to the "knowledge" of Seller shall
refer only to the current actual knowledge of the Designated Employees (as
hereinafter defined) of Seller, and shall not be construed, by imputation or
otherwise, to refer to the knowledge of Seller or any affiliate of Seller, to
any property manager, or to any other officer, agent, manager, representative or
employee of Seller or any affiliate thereof or to impose upon such Designated
Employees any duty to investigate the matter to which such actual knowledge, or
the absence thereof, pertains. As used herein, the term "DESIGNATED EMPLOYEES"
shall refer to Evan Boris and Chuck Gillum. Furthermore, Seller's
representations and warranties shall be deemed to be modified to reflect any
facts or circumstances disclosed in the Tenant Estoppels received by Purchaser.

        5.3     LEGAL REQUIREMENTS DEFINED. References to "Legal Requirements"
shall mean all laws, statutes, codes, acts, ordinances, orders, judgments,
decrees, injunctions, rules, regulations, Permits, licenses, authorizations,
directions and requirements of governmental authorities or quasi-governmental
authorities, which now or at any time hereafter exercise jurisdiction over the
Property, or any use, operation or condition of the Property.

        5.4     INTENTIONALLY OMITTED

        5.5     SURVIVAL OF SELLER'S REPRESENTATIONS, WARRANTIES AND OTHER
OBLIGATIONS. The representations and warranties of Seller set forth in Section
5.1 hereof as updated as of the Closing in accordance with the terms of this
Agreement, shall survive Closing for a period of two hundred seventy (270) days
after Closing. No claim for a breach of any representation, warranty, covenant
or agreement of Seller under this Agreement or any other instrument delivered to
Purchaser under or pursuant to this Agreement shall be actionable or payable if
the breach in question results from or is based on a condition, state of facts
or other matter which was known to Purchaser prior to Closing (including,
without limitation, pursuant to the terms of Section 4.2(f) above or if the
truth of any matter is confirmed in any Tenant Estoppel or other estoppel
certificate received by Purchaser from a third party). Seller shall have no
liability to Purchaser for a breach of any representation, warranty, covenant or
agreement (a) unless the valid claims for all such breaches collectively
aggregate more than Fifty Thousand and No/100 Dollars ($50,000.00) in which
event the full amount of such valid claims shall be actionable up to, but not in
excess of Two Million and No/100 Dollars ($2,000,000.00) (the "CAP") absent
fraud or intentional misrepresentation, and (b) unless written notice containing

<PAGE>

a description of the specific nature of such breach shall have been given by
Purchaser to Seller prior to the expiration of and an action shall have been
commenced by Purchaser against Seller within sixty (60) days after expiration of
such two hundred seventy (270) day period. Purchaser agrees to first seek
recovery under any insurance policies, service contracts, Tenant Estoppels and
Leases prior to seeking recovery from Seller, and Seller shall not be liable to
Purchaser if Purchaser's claim is satisfied from such insurance policies,
service contracts or Leases. In no event shall Seller be liable for any
consequential or punitive damages or for any damages in excess of the Cap.

        5.6     COVENANTS OF SELLER. Seller hereby covenants with Purchaser as
follows:

                (a)     From the Effective Date hereof until the Closing or
        earlier termination of this Agreement, Seller shall use reasonable
        efforts to operate and maintain the Property in a manner generally
        consistent with the manner in which Seller has operated and maintained
        the Property prior to the date hereof;

                (b)     Except as provided in this Section 5.6(b), a copy of any
        amendment, renewal or expansion of an existing Lease or of any new Lease
        which Seller in good faith wishes to execute between the Effective Date
        and the Closing Date will be submitted to Purchaser prior to execution
        by Seller. While this Agreement is in effect, Seller shall not enter
        into any new Lease or amend any existing Lease without the approval of
        Purchaser, such approval not to be unreasonably withheld, delayed or
        conditioned. Purchaser agrees to notify Seller in writing within five
        (5) business days after its receipt thereof of either its approval or
        disapproval thereof, including all Tenant Inducement Costs and
        Commissions to be incurred in connection therewith. Prior to the
        expiration of the Inspection Period, in the event Purchaser informs
        Seller within such five business day period that Purchaser does not
        approve the amendment, renewal or expansion of the existing Lease or the
        new Lease, which approval shall not be unreasonably withheld, Seller
        shall have the right to terminate this Agreement by written notice
        thereof to Purchaser within five (5) business days after Seller's
        receipt of written notice of Purchaser's disapproval thereof. If this
        Agreement is terminated pursuant to the foregoing provisions of this
        paragraph, then neither party shall have any further rights or
        obligations hereunder (except for any obligations of either party which
        expressly survive the termination of this Agreement), the Deposit shall
        be returned to Purchaser and each party shall bear its own costs
        incurred hereunder. In the event Purchaser fails to notify Seller in
        writing of its approval or disapproval within the five (5) business day
        period set forth above, Purchaser shall be deemed to have approved such
        new Lease, amendment, renewal or expansion. At Closing, Purchaser shall
        reimburse Seller for any Tenant Inducement Costs, Commissions or other
        expenses, including legal fees, incurred by Seller pursuant to an
        amendment, a renewal, an expansion or a new Lease approved (or deemed
        approved) by Purchaser, including, without limitation, the M&M Extension
        Lease. Notwithstanding the foregoing, (x) Purchaser shall have no right
        to approve any amendment to an Existing Lease entered into by Seller
        which evidences the exercise by a Tenant of a right or option granted to
        such Tenant in its Lease and (y) Purchaser shall have no right to
        approve the M&M Extension Lease so long as the M&M Extension

<PAGE>

        Lease (i) contains rental and other terms no less favorable to the
        landlord than those set forth on SCHEDULE 1; and (ii) contains terms and
        provisions consistent with (or more favorable to landlord than) those
        contained in M&M's existing lease at the Building or those contained in
        other leases at the Building; otherwise, Purchaser shall have the right
        to approve the M&M Extension Lease, which approval shall not be
        unreasonably withheld, delayed or conditioned, and if Purchaser shall
        fail to notify Seller of Purchaser's approval or disapproval of the M&M
        Extension Lease within five (5) business days after Purchaser's receipt
        thereof, then Purchaser shall be deemed to have approved the M&M
        Extension Lease.

                (c)     Seller shall notify Purchaser promptly if Seller becomes
        aware of any transaction or occurrence prior to the Closing Date which
        would affect the truth or accuracy of any representation or warranty of
        Seller contained in Section 5.1 hereof in a manner that would have a
        Material Adverse Effect and which Seller does not, in its reasonable
        opinion, believe can be cured prior to the Closing Date.

        5.7     REPRESENTATIONS AND WARRANTIES OF PURCHASER. Purchaser hereby
makes the following representations and warranties to Seller as of the Effective
Date, which representations and warranties shall be deemed to have been made
again as of the Closing, subject to Section 4.3(c) hereof:

                (a)     ORGANIZATION AND AUTHORITY. Purchaser has been duly
        organized and is validly existing under the laws of Texas. Purchaser has
        the full right and authority to enter into this Agreement and to
        consummate or cause to be consummated the transaction contemplated by
        this Agreement. The person signing this Agreement on behalf of Purchaser
        is authorized to do so; and

                (b)     PENDING ACTIONS. To Purchaser's knowledge, there is no
        action, suit, arbitration, unsatisfied order or judgment, government
        investigation or proceeding pending against Purchaser.

        5.8     SURVIVAL OF PURCHASER'S REPRESENTATIONS AND WARRANTIES. The
representations and warranties of Purchaser set forth in Section 5.5 hereof as
updated as of the Closing Date in accordance with the terms of this Agreement,
shall survive Closing for a period of one (1) year. Purchaser shall have no
liability to Seller for a breach of any representation or warranty unless
written notice containing a description of the specific nature of such breach
shall have been given by Seller to Purchaser prior to the expiration of said one
(1) year and an action shall have been commenced by Seller against Purchaser
within sixty (60) days after such one (1) year period.

<PAGE>

                                   ARTICLE VI

                                     DEFAULT

        6.1     DEFAULT BY PURCHASER. In the event Purchaser fails to close the
purchase of the Property when legally required to do so, Seller shall be
entitled, as its sole remedy, to terminate this Agreement and receive the
Deposit as liquidated damages for the breach of this Agreement, it being agreed
between the parties hereto that the actual damages to Seller in the event of
such breach are impractical to ascertain and the amount of the Deposit is a
reasonable estimate thereof.

        6.2     DEFAULT BY SELLER. In the event Seller fails to close the sale
of the Property when legally required to do so, Purchaser shall be entitled, as
its sole remedy, either (a) to receive the return of the Deposit, which return
shall operate to terminate this Agreement and release Seller and from any and
all liability hereunder, or (b) to enforce specific performance of Seller's
obligations to Purchaser in accordance with the terms of this Agreement.
Purchaser expressly waives its rights to seek damages in the event of Seller's
default hereunder. Purchaser shall be deemed to have elected to terminate this
Agreement and receive back the Deposit if Purchaser fails to file suit for
specific performance against Seller in a court having jurisdiction in the county
and state in which the Property is located, on or before sixty (60) days
following the date upon which Closing was to have occurred. Notwithstanding the
foregoing, if the remedy of specific performance is not legally available to
Purchaser solely due to Seller's transfer of the Property to a third person who
is not controlled by Seller or its Affiliates and who is not subject to the
terms and conditions of this Agreement, then Purchaser shall be entitled to the
prompt return of the Deposit and to seek an action for actual damages against
Seller as a result of such material default by Seller under this Agreement.

        6.3     RECOVERABLE DAMAGES. Notwithstanding Sections 6.1 and 6.2
hereof, in no event shall the provisions of Sections 6.1 and 6.2 limit the
damages recoverable by either party against the other party due to the other
party's obligation to indemnify such party in accordance with this Agreement.

                                   ARTICLE VII

                                  RISK OF LOSS

        7.1     MINOR DAMAGE. In the event of loss or damage to the Property or
any portion thereof which is not "Major" (as hereinafter defined), this
Agreement shall remain in full force and effect provided that Seller shall, at
Seller's option, either (a) perform any necessary repairs, or (b) assign to
Purchaser all of Seller's right, title and interest in and to any claims and
proceeds Seller may have with respect to any casualty insurance policies or
condemnation awards relating to the premises in question. In the event that
Seller elects to perform repairs upon the Property, Seller shall use reasonable
efforts to complete such repairs promptly and the Closing Date shall be extended
a reasonable time in order to allow for the completion of such repairs. If
Seller elects to assign a casualty claim to Purchaser, the Purchase Price shall

<PAGE>

be reduced by an amount equal to the lesser of the deductible amount under
Seller's insurance policy and the cost to complete the repairs. Upon Closing,
full risk of loss with respect to the Property shall pass to Purchaser.

        7.2     MAJOR DAMAGE. In the event of a "Major" loss or damage, either
Seller or Purchaser may terminate this Agreement by written notice to the other
party, in which event the Deposit shall be returned to Purchaser. If neither
Seller nor Purchaser elects to terminate this Agreement within ten (10) days
after Seller sends Purchaser written notice of the occurrence of such Major loss
or damage or threatened Major loss or damage in the case of condemnation or
eminent domain proceedings (which notice shall state the cost of repair or
restoration thereof as opined by an architect in accordance with Section 7.3
hereof), then Seller and Purchaser shall be deemed to have elected to proceed
with Closing, in which event Seller shall, at Seller's option, either (a)
perform any necessary repairs, or (b) assign to Purchaser all of Seller's right,
title and interest in and to any claims and proceeds Seller may have with
respect to any casualty insurance policies or condemnation awards and the
proceeds of any rent loss insurance relating to the premises in question. In the
event that Seller elects to perform repairs upon the Property, Seller shall use
reasonable efforts to complete such repairs promptly and the Closing Date shall
be extended a reasonable time in order to allow for the completion of such
repairs. If Seller elects to assign a casualty claim to Purchaser, the Purchase
Price shall be reduced by an amount equal to the deductible amount under
Seller's insurance policy. Upon Closing, full risk of loss with respect to the
Property shall pass to Purchaser.

        7.3     DEFINITION OF "MAJOR" LOSS OR DAMAGE. For purposes of Sections
7.1 and 7.2, "MAJOR" loss or damage refers to the following: (a) loss or damage
to the Property hereof such that the cost of repairing or restoring the premises
in question to substantially the same condition which existed prior to the event
of damage, in the opinion of an architect selected by Seller and reasonably
approved by Purchaser, either (i) would be equal to or greater than Five Hundred
Thousand and No/100 Dollars ($500,000.00), or (ii) could not reasonably be
repaired or restored within one hundred eighty (180) days after the date of
casualty, (b) any loss due to a condemnation or threatened condemnation which
could or will permanently and materially impair the current and intended use of
the Property, or (c) any loss, damage, condemnation or threat of condemnation
which gives rise to a right of termination of a lease in favor of any tenant
unless waived in writing by such tenant or which gives rise to abatement of rent
not covered by rent loss insurance that will inure to Purchaser's benefit after
Closing. If Purchaser does not give written notice to Seller of Purchaser's
reasons for disapproving an architect within five (5) business days after
receipt of notice of the proposed architect, Purchaser shall be deemed to have
approved the architect selected by Seller.

                                  ARTICLE VIII

                                   COMMISSIONS

        8.1     BROKERAGE COMMISSIONS. With respect to the transaction
contemplated by this Agreement, Seller represents that it has not engaged any
broker in connection with this transaction and Purchaser represents that it has
not engaged any broker in connection with this

<PAGE>

transaction. Each party hereto agrees that if any person or entity makes a claim
for brokerage commissions or finder's fees related to the sale of the Property
by Seller to Purchaser, and such claim is made by, through or on account of any
acts or alleged acts of said party or its representatives, said party will
protect, indemnify, defend and hold the other party free and harmless from and
against any and all loss, liability, cost, damage and expense (including
reasonable attorneys' fees) in connection therewith. The provisions of this
paragraph shall survive Closing or any termination of this Agreement.

                                   ARTICLE IX

                             DISCLAIMERS AND WAIVERS

        9.1     NO RELIANCE ON DOCUMENTS. Except as expressly stated herein or
in the documents to be executed by Seller and delivered to Purchaser in
connection with the Closing, Seller makes no representation or warranty as to
the truth, accuracy or completeness of any materials, data or information
delivered by Seller or its brokers or agents to Purchaser in connection with the
transaction contemplated hereby. Purchaser acknowledges and agrees that all
materials, data and information delivered by Seller to Purchaser in connection
with the transaction contemplated hereby are provided to Purchaser as a
convenience only and that any reliance on or use of such materials, data or
information by Purchaser shall be at the sole risk of Purchaser, except as
otherwise expressly stated herein. Neither Seller, nor any affiliate of Seller,
nor the person or entity which prepared any report or reports delivered by
Seller to Purchaser shall have any liability to Purchaser for any inaccuracy in
or omission from any such reports.

        9.2     AS-IS SALE; DISCLAIMERS. EXCEPT AS EXPRESSLY SET FORTH IN THIS
AGREEMENT, IT IS UNDERSTOOD AND AGREED THAT SELLER IS NOT MAKING AND HAS NOT AT
ANY TIME MADE ANY WARRANTIES OR REPRESENTATIONS OF ANY KIND OR CHARACTER,
EXPRESS OR IMPLIED, WITH RESPECT TO THE PROPERTY, INCLUDING, BUT NOT LIMITED TO,
ANY WARRANTIES OR REPRESENTATIONS AS TO HABITABILITY, MERCHANTABILITY OR FITNESS
FOR A PARTICULAR PURPOSE.

        PURCHASER ACKNOWLEDGES AND AGREES THAT UPON CLOSING SELLER SHALL SELL
AND CONVEY TO PURCHASER AND PURCHASER SHALL ACCEPT THE PROPERTY "AS IS, WHERE
IS, WITH ALL FAULTS." EXCEPT TO THE EXTENT EXPRESSLY PROVIDED OTHERWISE IN THIS
AGREEMENT OR THE DOCUMENTS EXECUTED AND DELIVERED AT CLOSING TO CONSUMMATE THIS
AGREEMENT, PURCHASER HAS NOT RELIED AND WILL NOT RELY ON, AND SELLER IS NOT
LIABLE FOR OR BOUND BY, ANY EXPRESS OR IMPLIED WARRANTIES, GUARANTIES,
STATEMENTS, REPRESENTATIONS OR INFORMATION PERTAINING TO THE PROPERTY OR
RELATING THERETO (INCLUDING SPECIFICALLY, WITHOUT LIMITATION, OFFERING PACKAGES
DISTRIBUTED WITH RESPECT TO THE PROPERTY) MADE OR FURNISHED BY SELLER, THE
MANAGERS OF THE PROPERTY, OR ANY REAL ESTATE BROKER OR AGENT REPRESENTING OR

<PAGE>

PURPORTING TO REPRESENT SELLER, TO WHOMEVER MADE OR GIVEN, DIRECTLY OR
INDIRECTLY, ORALLY OR IN WRITING, UNLESS SPECIFICALLY SET FORTH IN THIS
AGREEMENT.

        PURCHASER REPRESENTS TO SELLER THAT PURCHASER HAS CONDUCTED, OR WILL
CONDUCT PRIOR TO CLOSING, SUCH INVESTIGATIONS OF THE PROPERTY, INCLUDING BUT NOT
LIMITED TO, THE PHYSICAL AND ENVIRONMENTAL CONDITIONS THEREOF, AS PURCHASER
DEEMS NECESSARY OR DESIRABLE TO SATISFY ITSELF AS TO THE CONDITION OF THE
PROPERTY AND THE EXISTENCE OR NONEXISTENCE OR CURATIVE ACTION TO BE TAKEN WITH
RESPECT TO ANY HAZARDOUS OR TOXIC SUBSTANCES ON OR DISCHARGED FROM THE PROPERTY,
AND WILL RELY SOLELY UPON SAME AND NOT UPON ANY INFORMATION PROVIDED BY OR ON
BEHALF OF SELLER OR ITS AGENTS OR EMPLOYEES WITH RESPECT THERETO, OTHER THAN
SUCH REPRESENTATIONS, WARRANTIES AND COVENANTS OF SELLER AS ARE EXPRESSLY SET
FORTH IN THIS AGREEMENT OR THE DOCUMENTS EXECUTED AND DELIVERED AT CLOSING TO
CONSUMMATE THIS AGREEMENT. UPON CLOSING, PURCHASER SHALL ASSUME THE RISK THAT
ADVERSE MATTERS, INCLUDING BUT NOT LIMITED TO, CONSTRUCTION DEFECTS AND ADVERSE
PHYSICAL AND ENVIRONMENTAL CONDITIONS, MAY NOT HAVE BEEN REVEALED BY PURCHASER'S
INVESTIGATIONS AND PURCHASER, UPON CLOSING, SHALL BE DEEMED TO HAVE WAIVED,
RELINQUISHED AND RELEASED SELLER (AND SELLER'S OFFICERS, DIRECTORS,
SHAREHOLDERS, EMPLOYEES AND AGENTS) FROM AND AGAINST ANY AND ALL CLAIMS,
DEMANDS, CAUSES OF ACTION (INCLUDING CAUSES OF ACTION IN TORT), LOSSES, DAMAGES,
LIABILITIES, COSTS AND EXPENSES (INCLUDING REASONABLE ATTORNEYS' FEES) OF ANY
AND EVERY KIND OR CHARACTER, KNOWN OR UNKNOWN, WHICH PURCHASER MIGHT HAVE
ASSERTED OR ALLEGED AGAINST SELLER (OR SELLER'S OFFICERS, DIRECTORS,
SHAREHOLDERS, EMPLOYEES OR AGENTS) AT ANY TIME BY REASON OF OR ARISING OUT OF
ANY LATENT OR PATENT CONSTRUCTION DEFECTS OR PHYSICAL OR ENVIRONMENTAL
CONDITIONS, VIOLATIONS OF ANY APPLICABLE LAWS AND ANY AND ALL OTHER ACTS,
OMISSIONS, EVENTS, CIRCUMSTANCES OR MATTERS REGARDING THE PROPERTY.

        9.3     SURVIVAL OF DISCLAIMERS. The provisions of this Article IX shall
survive Closing or any termination of this Agreement.

                                    ARTICLE X

                                  MISCELLANEOUS

        10.1    CONFIDENTIALITY. Purchaser and its representatives shall hold in
strictest confidence all data and information obtained with respect to Seller or
its business, whether obtained before or after the execution and delivery of
this Agreement, and shall not disclose the

<PAGE>

same to others; provided, however, that it is understood and agreed that
Purchaser may disclose such data and information to its directors, employees,
consultants, accountants, attorneys and prospective lenders and investors of
Purchaser provided that such persons agree in writing to treat such data and
information confidentially, provided, however, Purchaser shall be permitted to
make such disclosures as may be recommended by Purchaser's legal counsel in
order to comply with all financial reporting, securities laws and other Legal
Requirements applicable to Purchaser. In the event this Agreement is terminated
or Purchaser fails to perform hereunder, Purchaser shall promptly return to
Seller any statements, documents, schedules, exhibits or other written
information obtained from Seller in connection with this Agreement or the
transaction contemplated herein. It is understood and agreed that, with respect
to any provision of this Agreement which refers to the termination of this
Agreement and the return of the Deposit to Purchaser, such Deposit shall not be
returned to Purchaser unless and until Purchaser has fulfilled its obligation to
return to Seller the materials described in the preceding sentence. In the event
of a breach or threatened breach by Purchaser or its agents or representatives
of this Section 10.1, Seller shall be entitled to an injunction restraining
Purchaser or its agents or representatives from disclosing, in whole or in part,
such confidential information. Nothing herein shall be construed as prohibiting
Seller from pursuing any other available remedy at law or in equity for such
breach or threatened breach. The provisions of this Section 10.1 shall survive
Closing or any termination of this Agreement.

        10.2    PUBLIC DISCLOSURE. Prior to and after the Closing, any release
to the public of information with respect to the sale contemplated herein or any
matters set forth in this Agreement will be made only in the form approved by
Purchaser and Seller; provided, however, Seller and Purchaser shall be permitted
to make such disclosures as may be recommended by Purchaser's legal counsel in
order to comply with all financial reporting, securities laws and other Legal
Requirements applicable to Purchaser and Seller. The provisions of this Section
10.2 shall survive the Closing or any termination of this Agreement.
Notwithstanding anything set forth in this Agreement to the contrary or in any
other agreement to which a party hereto is bound, each such party is (and any
employee, representative or other agent of such party is) hereby expressly
authorized to disclose the "tax treatment" or "tax structure" (as those terms
are defined in Treas. Reg. ss.ss.1.6011-4(c)(8) and (9), respectively) of the
transactions the subject of this Agreement and all materials of any kind
(including tax opinions or other tax analyses) that are provided to any such
party relating to such "tax treatment" or "tax structure" of the transactions
the subject of this Agreement, except that "tax treatment" or "tax structure"
shall not include the identify of any existing or future party to this Agreement
or their affiliates.

        10.3    ASSIGNMENT. Subject to the provisions of this Section 10.3, the
terms and provisions of this Agreement are to apply to and bind the permitted
successors and assigns of the parties hereto. Purchaser shall have the right,
exercised by written notice to Seller delivered at any time prior to Closing and
subject to the Assignment Procedures, to assign its rights under this Agreement
to an Affiliate of Purchaser. Except as set forth in the preceding sentence,
Purchaser may not assign its rights under this Agreement without first obtaining
Seller's written approval, which approval may be granted or withheld in Seller's
sole discretion. In the event Purchaser intends to assign its rights hereunder
the following shall apply (the "ASSIGNMENT PROCEDURES"): (a) Purchaser and the
proposed assignee shall execute an assignment and

<PAGE>

assumption of this Agreement in form and substance reasonably satisfactory to
Seller, and (b) in no event shall any assignment of this Agreement release or
discharge Purchaser from any liability or obligation hereunder. "AFFILIATE"
shall mean, with respect to any specified entity, an entity that controls, is
controlled by, or is under common control with such specified entity, with
control meaning the power through the ownership of voting securities by contract
or otherwise to direct the management and policies of such entity. It is
expressly agreed that any partnership in which the Purchaser or any Affiliate of
the Purchaser is the general partner and any fund sponsored by Purchaser or any
Affiliate of Purchaser shall be deemed to be an Affiliate of Purchaser. The
provisions of this Section 10.3 shall survive the Closing or any termination of
this Agreement.

        10.4    NOTICES. Any notice pursuant to this Agreement shall be given in
writing by (a) personal delivery, (b) reputable overnight delivery service with
proof of delivery, (c) United States Mail, postage prepaid, registered or
certified mail, return receipt requested, or (d) legible facsimile transmission,
sent to the intended addressee at the address set forth below, or to such other
address or to the attention of such other person as the addressee shall have
designated by written notice sent in accordance herewith, and shall be deemed to
have been given upon receipt or refusal to accept delivery, or, in the case of
facsimile transmission, as of the date of the facsimile transmission provided
that an original of such facsimile is also sent to the intended addressee by
means described in clauses (a), (b) or (c) above. Unless changed in accordance
with the preceding sentence, the addresses for notices given pursuant to this
Agreement shall be as follows:

                If to Seller:         c/o Trizec Properties, Inc.
                                      Sears Tower
                                      233 South Wacker Drive, Suite 4600
                                      Chicago, Illinois 60606
                                      Attention: Evan Boris
                                      Telephone No. (312) 466-3000
                                      Fax No. (312) 466-1710

                with a copy to:       Piper Rudnick
                                      203 North LaSalle Street, Suite 1800
                                      Chicago, Illinois  60601
                                      Attention: James L. Beard
                                      Telephone No. (312) 368-2169
                                      Fax No. (312) 630-7379
                                      Attention: Marsha D. Rubin
                                      Telephone No. (312) 368-3452
                                      Fax No. (312) 630-6348

<PAGE>

                If to Purchaser:      Harvard Property Trust, LLC
                                      1323 North Stemmons Freeway
                                      Dallas, Texas 75207
                                      Attention: Robert Behringer
                                      Telephone No. (214) 655-1600
                                      Fax No. (214) 655-1610

                with a copy to:       Powell & Coleman, L.L.P.
                                      8080 N. Central Expressway
                                      Suite 1380
                                      Dallas, Texas 75206
                                      Attention: Patrick Arnold
                                      Telephone No. (214) 890-7108
                                      Fax No. (214) 373-8768

        10.5    MODIFICATIONS. This Agreement cannot be changed orally, and no
executory agreement shall be effective to waive, change, modify or discharge it
in whole or in part unless such executory agreement is in writing and is signed
by the parties against whom enforcement of any waiver, change, modification or
discharge is sought.

        10.6    ENTIRE AGREEMENT. This Agreement, including the exhibits and
schedules hereto, contains the entire agreement between the parties hereto
pertaining to the subject matter hereof and fully supersedes all prior written
or oral agreements and understandings between the parties pertaining to such
subject matter, other than any confidentiality agreement executed by Purchaser
in connection with the Property. Seller agrees that it will make any reasonable
changes to the Trizec Lease attached hereto as EXHIBIT Q and the Management
Agreement attached hereto as EXHIBIT R required by Purchaser's lender.

        10.7    FURTHER ASSURANCES. Each party agrees that it will execute and
deliver such other documents and take such other action, whether prior or
subsequent to Closing, as may be reasonably requested by the other party to
consummate the transaction contemplated by this Agreement so long as the same
imposes no additional liability on such party. The provisions of this Section
10.7 shall survive Closing.

        10.8    COUNTERPARTS. This Agreement may be executed in counterparts,
all such executed counterparts shall constitute the same agreement, and the
signature of any party to any counterpart shall be deemed a signature to, and
may be appended to, any other counterpart.

        10.9    FACSIMILE SIGNATURES. In order to expedite the transaction
contemplated herein, telecopied or facsimile signatures may be used in place of
original signatures on this Agreement. Seller and Purchaser intend to be bound
by the signatures on the telecopied document, are aware that the other party
will rely on the telecopied signatures, and hereby waive any defenses to the
enforcement of the terms of this Agreement based on the form of signature.

<PAGE>

        10.10   SEVERABILITY. If any provision of this Agreement is determined
by a court of competent jurisdiction to be invalid or unenforceable, the
remainder of this Agreement shall nonetheless remain in full force and effect;
provided that the invalidity or unenforceability of such provision does not
materially adversely affect the benefits accruing to any party hereunder.

        10.11   APPLICABLE LAW. This Agreement shall be governed by and
construed in accordance with the laws of the State in which the Property is
located. Purchaser and Seller agree that the provisions of this Section 10.11
shall survive the Closing or any termination of this Agreement.

        10.12   NO THIRD-PARTY BENEFICIARY. The provisions of this Agreement and
of the documents to be executed and delivered at Closing are and will be for the
benefit of Seller and Purchaser only and are not for the benefit of any third
party, and accordingly, no third party shall have the right to enforce the
provisions of this Agreement or of the documents to be executed and delivered at
Closing.

        10.13   CAPTIONS. The section headings appearing in this Agreement are
for convenience of reference only and are not intended, to any extent and for
any purpose, to limit or define the text of any section or any subsection
hereof.

        10.14   CONSTRUCTION. The parties acknowledge that the parties and their
counsel have reviewed and revised this Agreement and that the normal rule of
construction to the effect that any ambiguities are to be resolved against the
drafting party shall not be employed in the interpretation of this Agreement or
any exhibits or amendments hereto.

        10.15   RECORDATION. This Agreement may not be recorded by any party
hereto without the prior written consent of the other party hereto. The
provisions of this Section 10.15 shall survive the Closing or any termination of
this Agreement.

        10.16   LIKE KIND EXCHANGE.

                (a)     Seller, at its option, may elect to use the proceeds for
        the sale of the Property to purchase a replacement property as part of a
        like-kind exchange under Section 1031 of the Code. If Seller desires to
        sell the Property as part of such a like-kind exchange, Seller shall
        notify Purchaser no later than two (2) business days prior to the
        Closing Date. Provided Seller has so notified Purchaser, Purchaser
        agrees to cooperate with Seller to effect the like-kind exchange
        contemplated hereunder and to execute and deliver all documents which
        reasonably may be required to effectuate such exchange as a qualified
        transaction pursuant to Section 1031 of the Code; provided that: (i) the
        Closing shall not be delayed; (ii) Purchaser incurs no additional cost
        or liability in connection with the like-kind exchange; (iii) Seller
        pays all costs associated with the like-kind exchange; and (iv)
        Purchaser is not obligated to take title to any other property.
        Similarly, in the event that Purchaser elects to purchase the Property
        as part of a like kind exchange pursuant to Section 1031 of the Code
        (including, without limitation, a Section 1031 exchange involving
        tenancy in common interests), Seller agrees to cooperate with

<PAGE>

        Purchaser in connection therewith and to execute and deliver all
        documents which reasonably may be required to effectuate such exchange
        as a qualified transaction pursuant to Section 1031 of the Code;
        provided that: (i) the Closing shall not be delayed; (ii) Seller incurs
        no additional cost or liability in connection with the like-kind
        exchange; (iii) Purchaser pays all costs associated with the like-kind
        exchange; and (iv) Seller is not obligated to take title to any other
        property.

                (b)     Purchaser has advised Seller that Purchaser may solicit
        investments in the Property from investors that will acquire undivided
        interests in the Property and become tenants-in-common therein ("TIC
        INVESTORS"). Notwithstanding anything contained in this Agreement to the
        contrary, Seller and Purchaser agree as follows: (a) Purchaser shall
        have the right to distribute information about the Property and this
        Agreement to potential brokers and their advisors who may facilitate the
        sale of such tenant-in-common interests; provided, however, that until
        the M&M Extension Lease has been fully executed, Purchaser shall not
        distribute any information relating to M&M and its lease at the Property
        or any extension or modification thereof without the prior written
        consent of Seller, which may be withheld in Seller's sole discretion;
        (b) Purchaser shall have the right to assign its rights under this
        Agreement (including, without limitation, any rights arising under the
        Seller Representation Certificate) to TIC Investors that invest in the
        Property; (c) Purchaser shall have the right to modify the form of
        Tenant Estoppel Certificate attached hereto as EXHIBIT D so as to
        expressly include the TIC Investors that invest in the Property within
        the definition of "Purchaser," so long as Purchaser informs Seller of
        such modification at least three (3) business days prior to the
        expiration of the Inspection Period; and (d) with the prior approval of
        Seller, which approval shall not be unreasonably withheld, delayed or
        conditioned, Purchaser may undertake other activities to accommodate the
        sale of tenant in common interest and substitute TIC Investors for all
        or portion of the Purchaser's interests hereunder or in the Property.

        10.17   ATTORNEYS' FEES AND COSTS. In the event suit or action is
instituted to interpret or enforce the terms of this Agreement, or in connection
with any arbitration or mediation of any dispute, the prevailing party shall be
entitled to recover from the other party such sum as the court, arbitrator or
mediator may adjudge reasonable as such party's costs and attorney's fees,
including such costs and fees as are incurred in any trial, on any appeal, in
any bankruptcy proceeding (including the adjudication of issues peculiar to
bankruptcy law) and in any petition for review. Each party shall also have the
right to recover its reasonable costs and attorney's fees incurred in collecting
any sum or debt owed to it by the other party, with or without litigation, if
such sum or debt is not paid within fifteen (15) days following written demand
therefor.

        10.18   GOVERNMENTAL APPROVALS. Nothing contained in this Agreement
shall be construed as authorizing Purchaser to apply for a zoning change,
variance, subdivision maps, lot line adjustment, or other discretionary
governmental act, approval or permit with respect to the Property prior to the
Closing, and Purchaser agrees not to do so. Purchaser agrees not to submit any
reports, studies or other documents, including, without limitation, plans and
specifications, impact statements for water, sewage, drainage or traffic,
environmental review forms, or energy

<PAGE>

conservation checklists to any governmental agency, or any amendment or
modification to any such instruments or documents prior to the Closing except to
the extent disclosure is required by applicable law. Purchaser's obligation to
purchase the Property shall not be subject to or conditioned upon Purchaser's
obtaining any variances, zoning amendments, subdivision maps, lot line
adjustment or other discretionary governmental act, approval or permit.

        10.19   EXCLUSIVE. Until this Agreement is terminated, Seller will cease
its marketing efforts and will not solicit, negotiate or enter into any backup
letters of intent, proposals, options or contracts with regard to the purchase
and sale of the Property.

        10.20   CALCULATION OF TIME PERIODS. In the event the date on which
Purchaser or Seller is required to take any action under the terms of this
Agreement is not a business day, the action will be taken on the next succeeding
business day.

        10.21   TIME OF ESSENCE. Seller and Purchaser hereby acknowledge and
agree that time is strictly of the essence with respect to each and every term,
condition, obligation and provision hereof.



                            [EXECUTION PAGE FOLLOWS]

<PAGE>

        IN WITNESS WHEREOF, the parties hereto have duly executed this Agreement
as of the Effective Date.


                                         SELLER:

                                         TRIZEC HOLDINGS, INC.,
                                         a Delaware corporation


                                         By:__________________________________
                                         Name:________________________________
                                         Its:_________________________________



                       [signatures continue on next page]

<PAGE>


                                         PURCHASER:

                                         BEHRINGER HARVARD OPERATING PARTNERSHIP
                                         I LP, a Texas limited partnership


                                         By:__________________________________
                                         Name:________________________________
                                         Its:_________________________________


                       [signatures continue on next page]

<PAGE>

        Escrow Agent executes this Agreement below solely for the purpose of
acknowledging that it agrees to be bound by the provisions of Sections 1.5 and
1.6 hereof.

                                         ESCROW AGENT:

                                         PARTNERS TITLE COMPANY


                                         By:__________________________________
                                         Name:________________________________
                                         Its:_________________________________