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                                                                    EXHIBIT 10.5


                                MERGER AGREEMENT

                          Dated as of April 30, 1997,

                                     Among

                        EQUITY OFFICE PROPERTIES TRUST,

                              ZML INVESTORS, INC.,

                            ZML INVESTORS II, INC.,

                         ZELL/MERRILL LYNCH REAL ESTATE
                         OPPORTUNITY PARTNERS III TRUST

                                      And

                         ZELL/MERRILL LYNCH REAL ESTATE
                         OPPORTUNITY PARTNERS IV TRUST




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     THIS MERGER AGREEMENT (this "Agreement") dated as of April 30, 1997 is made
and entered into among Equity Office Properties Trust, a Maryland real estate
investment trust (the "Company"), ZML Investors, Inc., a Delaware corporation
("ZML REIT I"), ZML Investors II, Inc., a Delaware corporation ("ZML REIT II"),
Zell/Merrill Lynch Real Estate Opportunity Partners III Trust, a Maryland real
estate investment trust ("ZML REIT III"), and Zell/Merrill Lynch Real Estate
Opportunity Partners IV Trust, a Maryland real estate investment trust ("ZML
REIT IV" and, together with ZML REIT I, ZML REIT II and ZML REIT III, the "ZML
REITs").

                                    RECITALS

     (a) Certain capitalized terms used herein shall have the meanings assigned
to them in Section 8.1.

     (b) The Boards of Directors or Boards of Trustees, as applicable, of the
Company and each of the ZML REITs and the shareholders of each of the ZML REITs
have approved the merger of each of the ZML REITs with and into the Company as
set forth below (the "Mergers"), upon the terms and subject to the conditions
set forth in this Agreement, whereby (i) each issued and outstanding share of
common stock, par value $.01 per share, of ZML REIT I (the "ZML I Common
Stock") will be converted into the right to receive the ZML I Merger
Consideration (as defined below); (ii) each issued and outstanding share of
Class A common stock, par value $.01 per share, of ZML REIT II (the "ZML II
Class A Common Stock") will be converted into the right to receive the ZML II
Class A Merger Consideration (as defined below); (iii) each issued and
outstanding share of Class B common stock, par value $.01 per share, of ZML
REIT II (the "ZML II Class B Common Stock," and together with the ZML II Class
A Common Stock the "ZML II Common Stock") will be converted into the right to
receive the ZML II Class B Contingent Merger Consideration (as defined below);
(iv) each issued and outstanding Class A common share of beneficial interest,
par value $.01 per share, of ZML REIT III (the "ZML III Class A Common Shares")
will be converted into the right to receive the ZML III Merger Consideration
(as defined below); (v) each issued and outstanding Class B share of beneficial
interest, par value $.01 per share, of ZML REIT III (the "ZML III Class B
Common Shares," and together with the ZML III Class A Common Shares the "ZML
III Common Shares") will be converted into the right to receive the ZML III
Class B Contingent Merger Consideration (as defined below); and (vi) each
issued and outstanding common share of beneficial interest, par value $.01 per
share, of ZML REIT IV (the "ZML IV Common Shares" and, together with the ZML I
Common Stock, the ZML II Common Stock and the ZML III Common Shares, the "ZML
REIT Shares") will be converted into the right to receive the ZML IV Merger
Consideration (as defined below).

     (c) The Company and each of the ZML REITs desire to make certain
representations, warranties, covenants and agreements in connection with the
Merger and also to prescribe various conditions to the Merger.

     (d) For federal income tax purposes it is intended that the Merger qualify
as a reorganization within the meaning of Section 368(a) of the Internal
Revenue Code of 1986, as amended (the "Code").



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     NOW, THEREFORE, in consideration of the representations, warranties,
covenants and agreements contained in this Agreement, the parties hereto agree
as follows:

ARTICLE I


THE MERGER

      SECTION 1.1  THE MERGER.

     Upon the terms and subject to the conditions set forth in this Agreement,
and in accordance with the corporation law of Delaware (the "Corporation Law")
and the Maryland General Corporation Law, as applicable to real estate
investment trusts ("MGCL"), each of the ZML REITs shall be merged with and into
the Company at the Effective Time.  Following the Merger, the separate
corporate existence of each of the ZML REITs shall cease and the Company shall
continue as the surviving corporation (the "Surviving Corporation") and shall
succeed to and assume all the rights and obligations of each ZML REIT in
accordance with the MGCL.

      SECTION 1.2  CLOSING.

     The closing of the Merger will take place at 10:00 a.m. on a date to be
specified by the parties, which (subject to satisfaction or waiver of the
conditions set forth in Sections 5.2 and 5.3) shall be no later than the second
business day after satisfaction or waiver of the conditions set forth in
Section 5.1 (the "Closing Date"), at the offices of Rosenberg & Liebentritt,
P.C., Two North Riverside Plaza, Suite 1515, Chicago, Illinois, unless another
date or place is agreed to by the parties hereto.


      SECTION 1.3  EFFECTIVE TIME.

     As soon as practicable following the satisfaction or waiver of the
conditions set forth in Article V, the parties shall file certificates of
merger or other appropriate documents (the "Certificates of Merger") executed
in accordance with the Corporation Law and articles of merger or other
appropriate documents (the "Articles of Merger") executed in accordance with
the MGCL and shall make all other filings or recordings required under the
Corporation Law or the MGCL.  The Merger shall become effective upon the later
of:  (i) the issuance of all certificates of merger by the State Department of
Assessments and Taxation of Maryland ("SDAT") in accordance with the MGCL and
(ii) the filing of the Certificates of Merger with the Secretary of State of
the State of Delaware, or at such later time which the Company and the ZML
REITs have agreed upon and designated in such filings in accordance with
applicable law (the time the Merger becomes effective being the "Effective
Time"), it being understood that the parties shall cause the Effective Time to
occur on the Closing Date.

      SECTION 1.4  EFFECTS OF THE MERGER.

     The Merger shall have the effects set forth in the Corporation Law and the
MGCL.




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      SECTION 1.5  DECLARATION OF TRUST.

     The Declaration of Trust of the Company, as in effect immediately prior to
the Effective Time, shall be the Declaration of Trust of the Surviving
Corporation, until duly amended in accordance with applicable law.  The Bylaws
of the Company, as in effect immediately prior to the Effective Time, shall be
the Bylaws of the Surviving Corporation.

ARTICLE II


EFFECT OF THE MERGER ON THE CAPITAL STOCK OF THE

CONSTITUENT CORPORATIONS AND REAL ESTATE INVESTMENT TRUSTS; EXCHANGE OF
CERTIFICATES

      SECTION 2.1  EFFECT ON CAPITAL STOCK.

     By virtue of the Merger and without any action on the part of the holder
of any ZML REIT Shares or the holder of any shares of beneficial interest of
the Company:

            (A) CANCELLATION OF TREASURY STOCK.

     As of the Effective Time, (i) any shares of capital stock of ZML REIT I
that are owned by ZML REIT I or any ZML I Subsidiary (as defined below), (ii)
any shares of capital stock of ZML REIT II that are owned by ZML REIT II or any
ZML II Subsidiary, (iii) any shares of beneficial interest of ZML REIT III that
are owned by ZML REIT III or any ZML III Subsidiary and (iv) any shares of
beneficial interest of ZML REIT IV that are owned by ZML REIT IV or any ZML IV
Subsidiary shall automatically be canceled and retired and all rights with
respect thereto shall cease to exist, and no consideration shall be delivered
in exchange therefor.

            (B) CONVERSION OF ZML I COMMON STOCK.

     Upon the Effective Time, each issued and outstanding share of ZML I Common
Stock (other than any shares to be canceled in accordance with Section 2.1(a))
shall be converted into the right to receive from the Company 51.56
fully paid and nonassessable common shares of beneficial interest, par value
$.01 per share, of the Company (each a "Company Common Share").  As of the
Effective Time, all shares of ZML I Common Stock shall no longer be outstanding
and shall automatically be canceled and retired and all rights with respect
thereto shall cease to exist, and each holder of a certificate representing any
such shares of ZML I Common Stock shall cease to have any rights with respect
thereto, except the right to receive, upon surrender of such certificate,
certificates representing the Company Common Shares required to be delivered
under this Section 2.1(b) and any cash in lieu of fractional shares of Company
Common Shares to be issued or paid in consideration therefor upon surrender of
such certificate (the "ZML I Merger Consideration") as set forth in Section
2.2(e), and any dividends or other distributions to which such holder is
entitled pursuant to Section 2.2(b), in each case without interest and less any
required withholding taxes.



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            (C) CONVERSION OF ZML II COMMON STOCK.

     Upon the Effective Time, (i) each issued and outstanding share of ZML II
Class A Common Stock (other than any shares to be canceled in accordance with
Section 2.1(a)) shall be converted into the right to receive from the Company
71.76 fully paid and nonassessable Company Common Shares, and (ii) each
issued and outstanding share of ZML II Class B Common Stock (other than any
shares to be canceled in accordance with Section 2.1(a)) shall be converted
into the right to receive one-one million two hundred seven thousand six
hundred thirty eighth (1/1,207,638) of any ZML II Class B Contingent Shares (as
defined in, and determined as set forth in, Section 2.4) (the "ZML II Class B
Contingent Merger Consideration").  As of the Effective Time, all shares of ZML
II Common Stock shall no longer be outstanding and shall automatically be
canceled and retired and all rights with respect thereto shall cease to exist,
and each holder of a certificate representing any such shares of ZML II Common
Stock shall cease to have any rights with respect thereto, except the right to
receive, upon surrender of such certificate, (x) in the case of the ZML II
Class A Common Stock, certificates representing the Company Common Shares
required to be delivered under this Section 2.1(c) and any cash in lieu of
fractional shares of Company Common Shares to be issued or paid in
consideration therefor upon surrender of such certificate (the "ZML II Class A
Merger Consideration") as set forth in Section 2.2(e), and any dividends or
other distributions to which such holder is entitled pursuant to Section
2.2(b), and (y) in the case of the ZML II Class B Common Stock, the ZML II
Class B Contingent Merger Consideration, if any, when and if payable, as
determined pursuant to Section 2.4, in each case without interest and less any
required withholding taxes.

            (D) CONVERSION OF ZML III COMMON SHARES.

     Upon the Effective Time, (i) each issued and outstanding ZML III Class A
Common Share (other than any shares to be canceled in accordance with Section
2.1(a)) shall be converted into the right to receive from the Company (i)
72.17 fully paid and nonassessable Company Common Shares, and (ii) each
issued and outstanding ZML III Class B Common Share (other than any shares to
be canceled in accordance with Section 2.1(a)) shall be converted into the
right to receive 1/692,290 of any ZML III Class B Contingent Shares (as
defined in, and determined as set forth in, Section 2.4) (the "ZML III Class B
Contingent Merger Consideration").  As of the Effective Time, all ZML III
Common Shares shall no longer be outstanding and shall automatically be
canceled and retired and all rights with respect thereto shall cease to exist,
and each holder of a certificate representing any such ZML III Common Shares
shall cease to have any rights with respect thereto, except the right to
receive, upon surrender of such certificate, (x) in the case of the ZML III
Class A Common Shares, certificates representing the Company Common Shares
required to be delivered under this Section 2.1(d) and any cash in lieu of
fractional shares of Company Common Shares to be issued or paid in
consideration therefor upon surrender of such certificate (the "ZML III Class A
Merger Consideration") as set forth in Section 2.2(e), and any dividends or
other distributions to which such holder is entitled pursuant to Section
2.2(b), and (y) in the case of the ZML III Class B Common Shares, the ZML III
Class B Contingent Merger Consideration, if any, when and if payable, as
determined pursuant to Section 2.4 in each case without interest and less any
required withholding taxes.



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            (E) CONVERSION OF ZML IV COMMON SHARES.

     Upon the Effective Time, each issued and outstanding ZML IV Common Share
(other than any shares to be canceled in accordance with Section 2.1(a)) shall
be converted into the right to receive from the Company 52.59 fully paid
and nonassessable Company Common Shares.  As of the Effective Time, all ZML IV
Common Shares shall no longer be outstanding and shall automatically be
canceled and retired and all rights with respect thereto shall cease to exist,
and each holder of a certificate representing any such ZML IV Common Shares
shall cease to have any rights with respect thereto, except the right to
receive, upon surrender of such certificate, certificates representing the
Company Common Shares required to be delivered under this Section 2.1(e) and
any cash in lieu of fractional shares of Company Common Shares to be issued or
paid in consideration therefor upon surrender of such certificate (the "ZML IV
Merger Consideration" and, together with the ZML I Merger Consideration, the
ZML II Class A Merger Consideration, the ZML II Class B Merger Consolidation,
ZML III Class A Merger Consideration, the ZML III Class B Contingent Merger
Consolidation, the "Merger Consideration") as set forth in Section 2.2(e), and
any dividends or other distributions to which such holder is entitled pursuant
to Section 2.2(b), in each case without interest and less any required
withholding taxes.

            (F) COMPANY COMMON SHARES.

     Upon the Effective Time, each Company Common Share outstanding immediately
prior to the Effective Time shall remain outstanding and shall represent one
validly issued, fully paid and nonassessable Company Common Share.

      SECTION 2.2  EXCHANGE OF CERTIFICATES.

            (A) EXCHANGE AGENT.

     Prior to the Effective Time, the Company shall appoint Boston Equiserv
L.P. or another bank or trust company reasonably acceptable to each of the ZML
REITs to act as exchange agent (the "Exchange Agent") for the exchange of the
Merger Consideration upon surrender of certificates representing issued and
outstanding ZML REIT Shares ("Certificates").  Each ZML REIT shall deposit with
the Exchange Agent, immediately prior to the Effective Time, from its own
assets (including, without limitation, distributions received by such ZML REIT
from the "opportunity partnership" in which such ZML REIT is a limited partner)
an amount of cash sufficient for the payment of the Final ZML REIT Dividend (as
defined in Section 2.2(b)) to be paid by such ZML REIT.  None of the cash to
pay the Final ZML REIT Dividends shall be provided, directly or indirectly, by
or from the assets of the Company.

            (B) RECORD DATES FOR FINAL DIVIDENDS; DISTRIBUTIONS WITH RESPECT TO
            UNEXCHANGED SHARES.

     (i) For the taxable year of each of the ZML REITs ending at the Effective
Time, each ZML REIT shall declare a dividend (each, a "Final ZML REIT
Dividend") to holders of such ZML REIT's ZML REIT Shares, the record date for
which shall be close of business on the last business day prior to the
Effective Time, in an amount equal to the minimum dividend sufficient to permit
such ZML REIT both to satisfy such requirements and to avoid any United States
federal income tax for such year (and any preceding taxable year) or


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any excise tax pursuant to Section 4982 of the Code.  The dividends payable
hereunder to holders of ZML REIT Shares shall be paid upon presentation of the
Certificates for exchange in accordance with this Article II.

     (ii) No dividends or other distributions with respect to Company Common
Shares with a record date after the Effective Time shall be paid to the holder
of any unsurrendered Certificate with respect to the Company Common Shares
represented thereby, and no cash payment in lieu of fractional shares shall be
paid to any such holder pursuant to Section 2.2(e), in each case until the
surrender of such Certificate in accordance with this Article II.  Subject to
the effect of applicable escheat laws, following surrender of any such
Certificate there shall be paid to the holder of such Certificate, without
interest, (i) at the time of such surrender, the amount of any cash payable in
lieu of any fractional Company Common Share to which such holder is entitled
pursuant to Section 2.2(e) and (ii) if such Certificate is exchangeable for one
or more whole Company Common Shares, (x) at the time of such surrender the
amount of dividends or other distributions with a record date after the
Effective Time theretofore paid with respect to such whole Company Common
Shares and (y) at the appropriate payment date, the amount of dividends or
other distributions with a record date after the Effective Time but prior to
such surrender and with a payment date subsequent to such surrender payable
with respect to such whole Company Common Shares.

            (C) NO FURTHER OWNERSHIP RIGHTS IN ZML REIT SHARES.

     All Merger Consideration payable upon the surrender of Certificates in
accordance with the terms of this Article II (and any cash paid pursuant to
Section 2.2(e)) (which shall including amounts payable as ZML II Class B
Contingent Merger Consideration and ZML III Class B Contingent Merger
Consolidation) shall be deemed to have been paid in full satisfaction of all
rights pertaining to the ZML REIT Shares theretofore represented by such
Certificates; provided, however, that each ZML REIT shall transfer to the
Exchange Agent cash sufficient to pay any dividends or make any other
distributions with a record date prior to the Effective Time which may have
been declared or made by such ZML REIT on such ZML REIT's respective ZML REIT
Shares in accordance with the terms of this Agreement or prior to the date of
this Agreement and which remain unpaid at the Effective Time and have not been
paid prior to such surrender, and there shall be no further registration of
transfers on the stock transfer books of any ZML REIT of the ZML REIT Shares
which were outstanding immediately prior to the Effective Time.  If, after the
Effective Time, Certificates are presented to the Surviving Corporation for any
reason, they shall be canceled and exchanged as provided in this Article II.

            (D) NO LIABILITY.

     None of the Company, the ZML REITs or the Exchange Agent shall be liable
to any person in respect of any Merger Consideration or dividends delivered to
a public official pursuant to any applicable abandoned property, escheat or
similar law.

            (E) NO FRACTIONAL SHARES.

     (i) No certificates or scrip representing fractional Company Common Shares
shall be issued upon the surrender for exchange of Certificates, and such
fractional


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share interests will not entitle the owner thereof to vote, to receive
dividends or to any other rights of a stockholder of the Company.

     (ii) Notwithstanding any other provision of this Agreement, each holder of
ZML REIT Shares exchanged pursuant to the Merger who would otherwise have been
entitled to receive a fraction of a Company Common Share (after taking into
account all Certificates delivered by such holder) shall receive, from the
Exchange Agent in accordance with the provisions of this Section 2.2(e), a cash
payment in lieu of such fractional Company Common Share, as applicable based on
the initial public offering price of the Company Common Shares.

      SECTION 2.3  ESCROW OF COMPANY COMMON SHARES.

     (i) Five percent (5%) of the Company Common Shares to be received by
each shareholder of ZML REIT I as part of the Merger Consideration and (ii) ten
percent (10%) of the Company Common Shares to be received by each shareholder
of ZML REIT II, ZML REIT III and ZML REIT IV as part of the Merger
Consideration (other than any Common Shares to be received as ZML II Class B
Contingent Consideration or ZML III Class B Contingent Consideration), shall be
deposited by the recipient shareholder into escrow on the Closing Date pursuant
to those certain Escrow Agreements dated as of July 11, 1997 between the
Company and State Street Bank and Trust Company, as escrow agent, relating to
each of the ZML REITs.  The Escrow Agreements are attached hereto as Exhibits
A.1, A.2, A.3 and A.4.  The Exchange Agent, as agent for such shareholders,
shall receive such Company Common Shares on behalf of the shareholders of the
ZML REITs and shall deliver them to State Street Bank and Trust Company, as
escrow agent, on behalf of such shareholders to hold and apply in accordance
with the terms of the applicable Escrow Agreement.

      SECTION 2.4  CONTINGENT ISSUANCE OF COMPANY COMMON SHARES.

            (A) ZML II CLASS B CONTINGENT CONSIDERATION.

     If the Company, as the successor to ZML REIT II, shall receive from
Zell/Merrill Lynch Real Estate Opportunity Partners Limited Partnership II
("Opportunity Partnership II") units of limited partnership interest in EOP
Operating Limited Partnership ("Units") that constitute a Class B Distribution
(as defined below), the Company shall issue one Company Common Share for each
such Unit received (each such Company Common Share is referred to as a ZML II
Class B Contingent Share).  The ZML II Class B Contingent Shares shall be
issued to the former holders of the ZML II Class B Common Stock at the
Effective Time of the Merger, with the holder of each share of ZML II Class B
Common Stock entitled to receive one-one million three hundred thirty-seven
thousand six hundred thirty eighth (1/1,337,638) of any ZML II Class B
Contingent Shares issued by the Company.  In lieu of any fractional ZML II
Class B Contingent Shares, each former holder of ZML II Class B Common Stock
who would be entitled to receive a fraction of a ZML II Class B Contingent
Share shall in lieu thereof receive a cash payment representing the fair value,
as determined by the Company, of such fraction of a ZML II Class B Contingent
Share.



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     Class B Distribution" shall mean with respect to Opportunity Partnership
II, any distribution to the Company pursuant to Section 5.04(C) or Section
5.05(C)(4) of the Agreement of Limited Partnership of Opportunity Partnership
II (the "Opportunity Partnership II Agreement") to the extent such distribution
is determined in accordance with ZML REIT II's Table 2.13(ii) Amount as set
forth in Section 2.13 of the Opportunity Partnership II Agreement .

            (B) ZML III CLASS B CONTINGENT CONSIDERATION.

     If the Company, as the successor to ZML REIT III, shall receive from
Zell Merrill Lynch Real Estate Opportunity Partners Limited Partnership III
("Opportunity Partnership III") Units  that constitute a Class B Distribution
(as defined below), the Company shall issue one Company Common Share for each
such Unit received (each such Company Common Share is referred to as a ZML III
Class B Contingent Share).  The ZML III Class B Contingent Shares shall be
issued to the former holders of the ZML III Class B Common Shares at the
Effective Time of the Merger, with the holder of each ZML III Class B Common
Share entitled to receive one-one million six hundred thirty-three thousand
three hundred twenty fifth (1/1,633,325) of any ZML III Class B Contingent
Shares issued by the Company.  In lieu of any fractional ZML III Class B
Contingent Shares, each former holder of ZML III Class B Common Shares who
would be entitled to receive a fraction of a ZML III Class B Contingent Share
shall in lieu thereof receive a cash payment representing the fair value, as
determined by the Company, of such fraction of a ZML III Class B Contingent
Share.

     "Class B Distribution" shall mean with respect to Opportunity Partnership
III, any distribution to the Company pursuant to Section 5.04(D) or Section
5.05(C)(4) of the Agreement of Limited Partnership of Opportunity Partnership
III (the "Opportunity Partnership III Agreement") to the extent such
distribution is determined in accordance with ZML REIT III's Table 2.14 Amount
as set forth in Section 2.14 of the Opportunity Partnership III Agreement.

ARTICLE III


REPRESENTATIONS AND WARRANTIES

      SECTION 3.1  REPRESENTATIONS AND WARRANTIES OF THE ZML REITS.

     Each ZML REIT represents and warrants as to itself to the Company as
follows:

            (A) ORGANIZATION, STANDING AND CORPORATE OR TRUST POWER OF ZML
            REIT.

     The ZML REIT is a corporation duly organized and validly existing under
the laws of Delaware or a real estate investment trust organized and validly
existing under the laws of Maryland, as applicable, and has the requisite
corporate or trust power and authority to carry on its business as now being
conducted.  The ZML REIT is duly qualified or licensed to do business and is in
good standing in each jurisdiction in which the nature of its business or the
ownership or leasing of its properties makes such qualification or licensing
necessary, other than in such jurisdictions where the failure to be so
qualified or licensed, individually or in the aggregate, would not have a
material adverse effect on the business, properties, assets, financial
condition or results of operations of the ZML REIT taken as a whole (a "ZML
REIT


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Material Adverse Effect").  The ZML REIT has delivered to the Company complete
and correct copies of its Certificate of Incorporation or Declaration of Trust,
as applicable, and Bylaws, each as amended to the date of this Agreement.

            (B) CAPITAL STRUCTURE.

     The authorized and, as of the date hereof, issued and outstanding capital
stock or shares of beneficial interest of the ZML REIT is as set forth on
Schedule 3.1(b) attached hereto.  On the date of this Agreement, except as set
forth on Schedule 3.1(b), no shares of capital stock or shares of beneficial
interest or other voting securities of the ZML REIT were issued, reserved for
issuance or outstanding.  There are no outstanding stock appreciation rights
relating to the capital stock or shares of beneficial interest of the ZML REIT.
All outstanding shares of capital stock or shares of beneficial interest of
the ZML REIT are duly authorized, validly issued, fully paid and nonassessable
and not subject to preemptive rights.  There are no bonds, debentures, notes or
other indebtedness of the ZML REIT having the right to vote (or convertible
into, or exchangeable for, securities having the right to vote) on any matters
on which shareholders of the ZML REIT may vote.  Except as set forth in
Schedule 3.1(b), as of the date of this Agreement there are no outstanding
securities, options, warrants, calls, rights, commitments, agreements,
arrangements or undertakings of any kind to which the ZML REIT is a party or by
which such entity is bound, obligating the ZML REIT to issue, deliver or sell,
or cause to be issued, delivered or sold, additional shares of capital stock or
shares of beneficial interest, voting securities or other ownership interests
of the ZML REIT or obligating the ZML REIT to issue, grant, extend or enter
into any such security, option, warrant, call, right, commitment, agreement,
arrangement or undertaking (other than to the ZML REIT).  Except as set forth
on Schedule 3.1(b), there are no outstanding contractual obligations of the ZML
REIT to repurchase, redeem or otherwise acquire any shares of capital stock or
shares of beneficial interest of the ZML REIT or make any material investment
(in the form of a loan, capital contribution or otherwise) in any person.

            (C) AUTHORITY; NONCONTRAVENTION; CONSENTS.

     The ZML REIT has the requisite corporate or trust power and authority to
enter into this Agreement and, including approval of this Agreement by the vote
of the holders of such ZML REIT's ZML REIT Shares required to approve this
Agreement and the transactions contemplated hereby (the "ZML REIT Shareholder
Approvals"), to consummate the transactions contemplated by this Agreement to
which the ZML REIT is a party.  The execution and delivery of this Agreement by
the ZML REIT and the consummation by the ZML REIT of the transactions
contemplated by this Agreement to which the ZML REIT is a party have been duly
authorized by all necessary corporate or trust action on the part of the ZML
REIT.  This Agreement has been duly executed and delivered by the ZML REIT and
constitutes a valid and binding obligation of the ZML REIT, enforceable against
the ZML REIT in accordance with its terms.  Except as set forth in Schedule
3.1(c) attached hereto, the execution and delivery of this Agreement by the ZML
REIT do not, and the consummation of the transactions contemplated by this
Agreement to which the ZML REIT is a party and compliance by the ZML REIT with
the provisions of this Agreement will not, conflict with, or result in any
violation of, or default (with or without notice or lapse of time, or both)
under, or give rise to a right of termination, cancellation or acceleration of
any obligation or to loss of a material benefit under, or result in the
creation of any lien upon any of the properties or assets of the ZML REIT
under, (i) the Certificate of Incorporation or Declaration of Trust, as
applicable, or the Bylaws of the ZML REIT, (ii) any loan


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or credit agreement, note, bond, mortgage, indenture, reciprocal easement
agreement, lease or other agreement, instrument, permit, concession, contract,
franchise or license applicable to the ZML REIT or its properties or assets or
(iii) subject to the governmental filings and other matters referred to in the
following sentence, any judgment, order, decree, statute, law, ordinance, rule
or regulation (collectively, "Laws") applicable to the ZML REIT or its
properties or assets, other than, in the case of clause (ii) or (iii), any such
conflicts, violations, defaults, rights or liens that individually or in the
aggregate would not (x) have a ZML REIT Material Adverse Effect or (y) prevent
the consummation of the transactions contemplated by this Agreement.  No
consent, approval, order or authorization of, or registration, declaration or
filing with, any federal, state or local government or any court,
administrative or regulatory agency or commission or other governmental
authority or agency, domestic or foreign (a "Governmental Entity"), is required
by or with respect to the ZML REIT in connection with the execution and
delivery of this Agreement by the ZML REIT or the consummation by the ZML REIT
of the transactions contemplated by this Agreement, except for (i) the filing
of the Articles of Merger with the SDAT and the Certificates of Merger with the
Secretary of State of the State of Delaware and (ii) such other consents,
approvals, orders, authorizations, registrations, declarations and filings (A)
as are set forth in Schedule 3.1(c), (B) as may be required under (x) federal,
state or local environmental laws or (y) the "blue sky" laws of various states
or (C) which, if not obtained or made, would not prevent or delay in any
material respect the consummation of any of the transactions contemplated by
this Agreement or otherwise prevent the ZML REIT from performing its
obligations under this Agreement in any material respect or have, individually
or in the aggregate, a ZML REIT Material Adverse Effect.

            (D) TAXES.

     (i) The ZML REIT has (A) filed all Tax returns and reports required to be
filed by it (after giving effect to any filing extension properly granted by a
Governmental Entity having authority to do so) and all such returns and reports
are accurate and complete in all material respects; and (B) paid all Taxes
shown on such returns and reports as required to be paid by it, and the most
recent financial statements of the ZML REIT reflect an adequate reserve for all
material Taxes payable by the ZML REIT for all taxable periods and portions
thereof through the date of such financial statements.  True, correct and
complete copies of all federal, state and local Tax returns and reports for the
ZML REIT, and all written communications relating thereto, have been delivered
or made available to representatives of the Company.  Since the date of the
last ZML REIT financial statements made available to the Company, the ZML REIT
has incurred no liability for taxes under Sections 857(b), 860(c) or 4981 of
the Code, and the ZML REIT has not incurred any material liability for Taxes
other than in the ordinary course of business.  To the knowledge of the ZML
REIT, no event has occurred, and no condition or circumstance exists, which
presents a material risk that any material Tax described in the preceding
sentence will be imposed upon the ZML REIT.  Except as set forth on Schedule
3.1(d) attached hereto, to the knowledge of the ZML REIT, no deficiencies for
any Taxes have been proposed, asserted or assessed against the ZML REIT, and no
requests for waivers of the time to assess any such Taxes are pending.  As used
in this Agreement, "Taxes" shall include all federal, state, local and foreign
income, property, sales, excise and other taxes, tariffs or governmental
charges of any nature whatsoever, together with penalties, interest or
additions to Tax with respect thereto.

     (ii) The ZML REIT (A) for all taxable years commencing with 1989, 1992,
1994 and 1996 for ZML REIT I, ZML REIT II, ZML REIT III and ZML REIT IV,


                                       10

<PAGE>   12


respectively, through December 31, 1996 has qualified for taxation as a real
estate investment trust (a "REIT") within the meaning of the Code, (B) has
operated, and intends to continue to operate, in such a manner as to qualify as
a REIT for the tax year ending December 31, 1997, and (C) has not taken or
omitted to take any action which would reasonably be expected to result in a
challenge to its status as a REIT, and to the ZML REIT's knowledge, no such
challenge is pending or threatened.  The ZML REIT does not hold any asset (x)
the disposition of which would be subject to rules similar to Section 1374 of
the Code as a result of an election under IRS Notice 88-19 or (y) that is
subject to a consent filed pursuant to Section 341(f) of the Code and the
regulations thereunder.

            (E) INVESTMENT COMPANY ACT OF 1940.

     The ZML REIT is not, and at the Effective Time will not be, required to be
registered under the Investment Company Act of 1940, as amended (the "1940
Act").

      SECTION 3.2  REPRESENTATIONS AND WARRANTIES OF THE COMPANY.

     The Company represents and warrants to each of the ZML REITs as follows:

            (A) ORGANIZATION, STANDING AND TRUST POWER OF THE COMPANY.

     The Company is a real estate investment trust duly organized and validly
existing under the laws of Maryland and has the requisite trust power and
authority to carry on its business as now being conducted.  The Company is duly
qualified or licensed to do business and is in good standing in each
jurisdiction in which the nature of its business or the ownership or leasing of
its properties makes such qualification or licensing necessary, other than in
such jurisdictions where the failure to be so qualified or licensed,
individually or in the aggregate, would not have a material adverse effect on
the business, properties, assets, financial condition or results of operations
of the Company taken as a whole (a "Company Material Adverse Effect").  The
Company has delivered to each of the ZML REITs complete and correct copies of
its Declaration of Trust and Bylaws, each as amended to the date of this
Agreement.

            (B) CAPITAL STRUCTURE.

     The authorized and, as of the date hereof, issued and outstanding capital
stock of the Company is as set forth on Schedule 3.2(b) attached hereto.  On
the date of this Agreement, except as set forth on Schedule 3.2(b), no shares
of capital stock or other voting securities of the Company were issued,
reserved for issuance or outstanding.  There are no outstanding stock
appreciation rights relating to the capital stock of the Company.  All
outstanding shares of capital stock of the Company are duly authorized, validly
issued, fully paid and nonassessable and not subject to preemptive rights.
There are no bonds, debentures, notes or other indebtedness of the Company
having the right to vote (or convertible into, or exchangeable for, securities
having the right to vote) on any matters on which shareholders of Company may
vote.  Except as set forth in Schedule 3.2(b), as of the date of this Agreement
there are no outstanding securities, options, warrants, calls, rights,
commitments, agreements, arrangements or undertakings of any kind to which the
Company is a party or by which such entity is bound, obligating the Company to
issue, deliver or sell, or cause to be issued, delivered or sold, additional
shares of capital stock, voting securities or other ownership interests of the


                                       11

<PAGE>   13


Company or obligating the Company to issue, grant, extend or enter into any
such security, option, warrant, call, right, commitment, agreement, arrangement
or undertaking (other than to the Company).  Except as set forth on Schedule
3.2(b), there are no outstanding contractual obligations of the Company to
repurchase, redeem or otherwise acquire any shares of capital stock of the
Company or make any material investment (in the form of a loan, capital
contribution or otherwise) in any person.

            (C) AUTHORITY; NONCONTRAVENTION; CONSENTS.

     The Company has the requisite trust power and authority to enter into this
Agreement and to consummate the transactions contemplated by this Agreement to
which the Company is a party.  The execution and delivery of this Agreement by
the Company and the consummation by the Company of the transactions
contemplated by this Agreement to which the Company is a party have been duly
authorized by all necessary trust action on the part of the Company.  This
Agreement has been duly executed and delivered by the Company and constitutes a
valid and binding obligation of the Company, enforceable against the Company in
accordance with its terms.  Except as set forth in Schedule 3.2(c) attached
hereto, the execution and delivery of this Agreement by the Company do not, and
the consummation of the transactions contemplated by this Agreement to which
the Company is a party and compliance by the Company with the provisions of
this Agreement will not, conflict with, or result in any violation of, or
default (with or without notice or lapse of time, or both) under, or give rise
to a right of termination, cancellation or acceleration of any obligation or to
loss of a material benefit under, or result in the creation of any lien upon
any of the properties or assets of the Company under, (i) the Declaration of
Trust or the Bylaws of the Company, (ii) any loan or credit agreement, note,
bond, mortgage, indenture, reciprocal easement agreement, lease or other
agreement, instrument, permit, concession, contract, franchise or license
applicable to the Company or its properties or assets or (iii) subject to the
governmental filings and other matters referred to in the following sentence,
any Laws applicable to the Company or its properties or assets, other than, in
the case of clause (ii) or (iii), any such conflicts, violations, defaults,
rights or liens that individually or in the aggregate would not (x) have a
Company Material Adverse Effect or (y) prevent the consummation of the
transactions contemplated by this Agreement.  No consent, approval, order or
authorization of, or registration, declaration or filing with, any Governmental
Entity is required by or with respect to the Company in connection with the
execution and delivery of this Agreement by the Company or the consummation by
the Company of the transactions contemplated by this Agreement, except for (i)
the filing of the Articles of Merger with the SDAT and the Certificates of
Merger with the Secretary of State of the State of Delaware and (ii) such other
consents, approvals, orders, authorizations, registrations, declarations and
filings (A) as are set forth in Schedule 3.2(c), (B) as may be required under
(x) federal, state or local environmental laws or (y) the "blue sky" laws of
various states or (C) which, if not obtained or made, would not prevent or
delay in any material respect the consummation of any of the transactions
contemplated by this Agreement or otherwise prevent the Company from performing
its obligations under this Agreement in any material respect or have,
individually or in the aggregate, a Company Material Adverse Effect.

            (D) TAXES.

     The Company is organized in conformity with the requirements for
qualification as a REIT under the Code, and the method of operation of the
Company will permit the


                                       12

<PAGE>   14


Company to meet the requirements for taxation as a REIT under the Code
beginning with its taxable year ending December 31, 1997 and continuing for its
subsequent taxable years.

            (E) INVESTMENT COMPANY ACT OF 1940.

     The Company is not, and at the Effective Time will not be, required to be
registered under the 1940 Act.

ARTICLE IV


COVENANTS

      SECTION 4.1  CONDUCT OF BUSINESS BY THE ZML REITS.

     During the period from the date of this Agreement to the Effective Time,
each of the ZML REITs shall carry on its businesses in the usual, regular and
ordinary course in substantially the same manner as heretofore conducted and,
to the extent consistent therewith, use commercially reasonable efforts to
preserve intact its current business organization, goodwill and ongoing
businesses.

      SECTION 4.2   TAX TREATMENT.

     Each of the ZML REITs and the Company shall use its reasonable best
efforts to cause the Merger to qualify as a reorganization under the provisions
of Section 368(a) of the Code.

ARTICLE V


CONDITIONS PRECEDENT

      SECTION 5.1  CONDITIONS TO EACH PARTY'S OBLIGATION TO EFFECT THE MERGER.

     The respective obligation of each party to effect the Merger and to
consummate the other transactions contemplated to occur on the Closing Date is
subject to the satisfaction or waiver on or prior to the Effective Time of the
following conditions:

            (A) LISTING OF SHARES.

     The New York Stock Exchange shall have approved for listing the Company
Common Shares to be issued in the Merger.

            (B) NO INJUNCTIONS OR RESTRAINTS.

     No temporary restraining order, preliminary or permanent injunction or
other order issued by any court of competent jurisdiction or other legal
restraint or prohibition


                                       13

<PAGE>   15


preventing the consummation of the Merger or any of the other transactions
contemplate hereby shall be in effect.

            (C) BLUE SKY LAWS.

     The Company shall have received all state securities or "blue sky" permits
and other authorizations necessary to issue the Company Common Shares
comprising the Merger Consideration.

            (D) CERTAIN ACTIONS AND CONSENTS.

     All material actions by or in respect of or filings with any Governmental
Entity required for the consummation of the transactions contemplated hereby
shall have been obtained or made.

            (E) ISSUANCE OF FAIRNESS OPINION.

     J.P. Morgan Securities, Inc. shall have delivered to the Board of Director
or Board of Trustees, as applicable, of each of the ZML REITs a fairness
opinion substantially in the form attached as Exhibit B hereto.

      SECTION 5.2  CONDITIONS TO OBLIGATION OF THE COMPANY.

     The obligation of the Company to effect the Merger and to consummate the
other transactions contemplated to occur on the Closing Date are further
subject to the following conditions, any one or more of which may be waived by
the Company:

            (A) REPRESENTATIONS AND WARRANTIES.

     The representations and warranties of each of the ZML REITs set forth in
this Agreement shall be true and correct as of the Closing Date, as though made
on and as of the Closing Date, except to the extent the representation or
warranty is expressly limited by its terms to another date, and the Company
shall have received certificates (which certificates may be qualified by
knowledge to the same extent as such representations and warranties are so
qualified) signed on behalf of each of the ZML REITs by the chief executive
officer or the chief financial officer of such ZML REIT to such effect.  This
condition shall be deemed satisfied unless any or all breaches of each ZML
REIT's representations and warranties in this Agreement (without giving effect
to any materiality qualification or limitation) is reasonably expected to have
a ZML REIT Material Adverse Effect.

            (B) MATERIAL ADVERSE CHANGE.

     Since the date of this Agreement, there shall have been no Material
Adverse Change as to any ZML REIT.

            (C) CONSENTS.

     All consents and waivers  from third parties described in Section 3.1(c)
shall have been obtained, other than such consents and waivers from third
parties, which, if not


                                       14

<PAGE>   16


obtained, would not result, individually or in the aggregate, in a ZML REIT
Material Adverse Effect or a Company Material Adverse Effect.

     Notwithstanding the foregoing, the Company shall not be obligated to
effect the Merger if the failure of one or more of the conditions set forth in
Sections 5.2(a), 5.2(b) and 5.2(c) to be satisfied, in the aggregate, causes a
Company Material Adverse Effect.

      SECTION 5.3  CONDITIONS TO OBLIGATIONS OF THE ZML REITS.

     The obligations of each of the ZML REITs to effect the Merger and to
consummate the other transactions contemplated to occur on the Closing Date is
further subject to the following conditions, any one or more of which may be
waived by each ZML REIT:

            (A) REPRESENTATIONS AND WARRANTIES.

     The representations and warranties of the Company set forth in this
Agreement shall be true and correct as of the date of this Agreement and as of
the Closing Date, as though made on and as of the Closing Date, except to the
extent the representation or warranty is expressly limited by its terms to
another date, and each ZML REIT shall have received a certificate (which
certificate may be qualified by knowledge to the same extent as the
representations and warranties of the Company contained herein are so
qualified) signed on behalf of the Company by the Company's chief executive
officer and chief financial officer to such effect.  This condition shall be
deemed satisfied unless any or all breaches of the Company's representations
and warranties in this Agreement (without giving effect to any materiality
qualification or limitation) is reasonably expected to have a Company Material
Adverse Effect.

            (B) CONSENTS.

     All consents and waivers from third parties described in Section 3.5(c)
shall have been obtained, other than such consents and waivers from third
parties, which, if not obtained, would not have a ZML REIT Material Adverse
Effect or a Company Material Adverse Effect.

     Notwithstanding the foregoing, no ZML REIT shall be obligated to effect
the Merger if the failure of one or more of the conditions set forth in
Sections 5.3(a) and 5.3(b) to be satisfied, in the aggregate, causes such ZML
REIT a ZML REIT Material Adverse Effect.



                                       15

<PAGE>   17


ARTICLE VI


SURVIVAL OF REPRESENTATIONS AND
WARRANTIES; REMEDIES; INDEMNIFICATION

     SECTION 6.1  SURVIVAL OF REPRESENTATIONS AND WARRANTIES; REMEDY FOR
                  BREACH.

     All of the representations and warranties contained in this Merger
Agreement or in any document delivered pursuant hereto shall survive the
Effective Time for a period of one (1) year from and after the Effective Time.
Any claim for indemnification under Section 6.3 must be asserted in writing by
the Indemnified Party, as the case may be, stating the nature of the Losses and
the basis for the indemnification therefor within one (1) year from and after
the Effective Time. If so asserted in writing within one (1) year from and
after the Effective Time, such claims for indemnification shall survive until
resolved by mutual agreement between the parties to such claim or until final
judicial determination.  Any claim for indemnification not so asserted in
writing within one (1) year from and after the Effective Time shall not
thereafter be asserted and shall forever be waived.

     SECTION 6.2  INDEMNIFICATION BY COMPANY.

     The Company hereby agrees to indemnify and hold harmless each of the ZML
REITs, each of their respective directors, officers, employees, agents,
representatives and affiliates (each an "Indemnified Party") from and against
any and all Losses asserted against, imposed upon or incurred by the
Indemnified Party in connection with any breach of a representation or warranty
of the Company contained in this Merger Agreement.

     SECTION 6.3  INDEMNIFICATION BY ZML REITS.

     Each ZML REIT hereby agrees to indemnify and hold harmless the Company and
its affiliates and each of their respective directors, managers, officers,
employees, agents, representatives and affiliates (each of which is an
"Indemnified Party") from and against any and all losses, claims, liabilities,
damages, costs and expenses ("Loss") asserted against, imposed upon or incurred
by the Indemnified Party in connection with or as a result of any breach of a
representation or warranty of such ZML REITs contained in this Merger Agreement
or in any document delivered by the ZML REITs pursuant to this Merger Agreement
(with any such breach being determined solely for purposes of this Section 6.3
without regard to whether such breach has a Material Adverse Effect on the
Company).

     SECTION 6.4  NOTICE AND DEFENSE OF CLAIMS.

     As soon as reasonably practicable after receipt by the Indemnified Party
of notice of any liability or claim incurred by or asserted against the
Indemnified Party that is subject to indemnification under this Section 6 the
Indemnified Party shall give notice thereof to the ZML REIT, including
liabilities or claims to be applied against the indemnification threshold
established pursuant to Section 6.5 hereof.  The Indemnified Party may at its
option demand indemnity under this Article VI as soon as a claim has been
threatened by a third party,


                                       16

<PAGE>   18


regardless of whether any actual Losses have been suffered, so long as the
Indemnified Party shall in good faith determine that such claim is not
frivolous and that the Indemnified Party may be liable for, or otherwise incur,
Losses as a result thereof and shall give notice of such determination to the
ZML REIT.  The Indemnified Party shall permit the ZML REIT, at its option and
expense, to assume the defense of any such claim by counsel selected by the ZML
REIT and reasonably satisfactory to the Indemnified Party, and to settle or
otherwise dispose of the same; provided, however, that the Indemnified Party
may at all times participate in such defense at its expense; and provided
further, however, that the ZML REIT shall not, in defense of any such claim,
except with the prior written consent of the Indemnified Party in its sole and
absolute discretion, consent to the entry of any judgment or enter into any
settlement that does not include as an unconditional term thereof the giving by
the claimant or plaintiff in question to the Indemnified Party and its
affiliates a release of all liabilities in respect of such claims, or that does
not result only in the payment of money damages.  If the ZML REIT shall fail to
undertake such defense within 30 days after such notice, or within such shorter
time as may be reasonable under the circumstances, then the Indemnified Party
shall have the right to undertake the defense, compromise or settlement of such
liability or claim on behalf of and for the account of the ZML REIT.

      SECTION 6.5  LIMITATIONS ON AND THRESHOLD FOR INDEMNIFICATION.

     (a) No ZML REIT shall be liable under Sections 3.1 or 6.3 hereof unless
and until the aggregate amount recoverable from Indemnifying Parties under the
indemnification provisions  set forth in Section 6.3 exceeds $250,000 provided,
however, that once the total amount recoverable from Indemnifying Parties
exceeds $250,000 in the aggregate, the ZML REIT's obligation under Section 6.3
shall be for the full amount of such obligation.

     (b) Notwithstanding anything contained herein to the contrary, no ZML REIT
shall be liable or obligated to make payments under this Agreement on any
document deliveries pursuant to its terms to the extent such payments; when
aggregated with any payments made by its subsidiary Opportunity Partnership
under Section 5.3 of the Contribution Agreement, would exceed the net
realizable value (calculated from time to time as of the date or dates on which
claims are paid hereunder) of one percent (1%) of the Company Common Shares
issued or which may be issued in exchange for Units issued to such Opportunity
Partnership pursuant to Section 1.3 of the Contribution Agreement.

ARTICLE VII


TERMINATION, AMENDMENT AND WAIVER

      SECTION 7.1  TERMINATION.

     This Agreement may be terminated at any time prior to the filing of the
Certificates of Merger with the Secretary of State of the State of Delaware and
the filing of the Articles of Merger with the SDAT:

     (a) by mutual written consent duly authorized by the respective Boards of
Directors or Boards of Trustees of each ZML REIT and the Company;



                                       17

<PAGE>   19


     (b) by the Company, upon a breach of any representation, warranty,
covenant or agreement on the part of any ZML REIT set forth in this Agreement,
or if any representation or warranty of the Company shall have become untrue,
in either case such that the condition set forth in Section 5.2(a) or 5.2(b),
as the case may be, would be incapable of being satisfied by March 31 , 1998
(or as otherwise extended);

     (c) by any ZML REIT, upon a breach of any representation, warranty,
covenant or agreement on the part of the Company set forth in this Agreement,
or if any representation or warranty of the Company shall have become untrue,
in either case such that the conditions set forth in Section 5.3(a) would be
incapable of being satisfied by March 31 , 1998 (or as otherwise extended);

     (d) by any ZML REIT or the Company, if any judgment, injunction, order,
decree or action by any Governmental Entity of competent authority preventing
the consummation of the Merger shall have become final and nonappealable; and

     (e) by any ZML REIT or the Company, if the Merger shall not have been
consummated before  March 31 , 1998; provided, however, that a party that has
willfully and materially breached a representation, warranty or covenant of
such party set forth in this Agreement shall not be entitled to exercise its
right to terminate under this Section 6.1(e).

      SECTION 7.2  EFFECT OF TERMINATION.

     In the event of termination of this Agreement by any ZML REIT or the
Company as provided in Section 7.1, this Agreement shall forthwith become void
and have no effect, without any liability or obligation on the part of any ZML
REIT or the Company, other than Article VI and except to the extent that such
termination results from a material breach by a party of any of its
representations, warranties, covenants or agreements set forth in this
Agreement.

      SECTION 7.3  AMENDMENT.

     This Agreement may be amended by the parties in writing by action of their
respective Boards of Directors or Boards of Trustees at any time before or
after any Shareholder Approvals are obtained and prior to the filing of the
Certificates of Merger with the Secretary of State of the State of Delaware and
the Articles of Merger with SDAT; provided, however, that, after the
Shareholder Approvals are obtained, no such amendment, modification or
supplement shall alter the amount or change the form of the consideration to be
delivered to each ZML REIT's shareholders or alter or change any of the terms
or conditions of this Agreement if such alteration or change would adversely
affect the Company's shareholders or any ZML REIT's shareholders.

      SECTION 7.4  EXTENSION; WAIVER.

     At any time prior to the Effective Time, the parties may (a) extend the
time for the performance of any of the obligations or other acts of the other
party, (b) waive any inaccuracies in the representations and warranties of the
other party contained in this Agreement or in any document delivered pursuant
to this Agreement or (c) subject to the


                                       18

<PAGE>   20


proviso of Section 7.3, waive compliance with any of the agreements or
conditions of the other party contained in this Agreement.  Any agreement on
the part of a party to any such extension or waiver shall be valid only if set
forth in an instrument in writing signed on behalf of such party.  The failure
of any party to this Agreement to assert any of its rights under this Agreement
or otherwise shall not constitute a waiver of those rights.

ARTICLE VIII


GENERAL PROVISIONS

      SECTION 8.1  CERTAIN DEFINITIONS.

            For purposes of this Agreement:

     "Material Adverse Change" means, with respect to a party hereto, any
change that would have a ZML REIT Material Adverse Effect or a Company Material
Adverse Effect, as applicable.

     "Subsidiary" of any person means any corporation, partnership, limited
liability company, joint venture or other legal entity of which such person
(either directly or through or together with another Subsidiary of such person)
owns 20% or more of the capital stock or other equity interests of such
corporation, partnership, limited liability company, joint venture or other
legal entity.

      SECTION 8.2  COUNTERPARTS.

     This Agreement may be executed in one or more counterparts, all of which
shall be considered one and the same agreement and shall become effective when
one or more counterparts have been signed by each of the parties and delivered
to the other parties.

      SECTION 8.3  GOVERNING LAW.

     THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE
LAWS OF THE STATE OF MARYLAND, REGARDLESS OF THE LAWS THAT MIGHT OTHERWISE
GOVERN UNDER APPLICABLE PRINCIPLES OF CONFLICT OF LAWS THEREOF, EXCEPT TO THE
EXTENT THAT THE MERGER OR OTHER TRANSACTIONS CONTEMPLATED HEREBY ARE REQUIRED
TO BE GOVERNED BY THE CORPORATION LAW.

      SECTION 8.4  ASSIGNMENT.

     Neither this Agreement nor any of the rights, interests or obligations
under this Agreement shall be assigned or delegated, in whole or in part, by
operation of law or otherwise by any of the parties without the prior written
consent of the other parties.  Subject to the preceding sentence, this
Agreement will be binding upon, inure to the benefit of, and be enforceable by,
the parties and their respective successors and assigns.



                                       19

<PAGE>   21


      SECTION 8.6  SEVERABILITY.

     If any provision of this Agreement is held to be illegal, invalid or
unenforceable under any current or future law, and if the rights or obligations
of the parties under this Agreement would not be materially and adversely
affected thereby, such provision shall be fully separable, and this Agreement
shall be construed and enforced as if such illegal, invalid or unenforceable
provision had never comprised a part thereof, the remaining provisions of this
Agreement shall remain in full force and effect and shall not be affected by
the illegal, invalid or unenforceable provision or by its severance therefrom.
In lieu of such illegal, invalid or unenforceable provision, there shall be
added automatically as a part of this Agreement, a legal, valid and enforceable
provision as similar in terms to such illegal, invalid or unenforceable
provision as may be possible, and the parties hereto request the court or any
arbitrator to whom disputes relating to this Agreement are submitted to reform
the otherwise illegal, invalid or unenforceable provision in accordance with
this Section 8.7.



                                       20

<PAGE>   22


     IN WITNESS WHEREOF, each of the Company, ZML REIT I, ZML REIT II, ZML REIT
III and ZML REIT IV has caused this Agreement to be signed by its respective
officers thereunto duly authorized, all as of the date first written above.

                                    Equity Office Properties Trust



                                    By:  /s/ Stanley M. Stevens
                                         ---------------------------
                                         Name: Stanley M. Stevens
                                         Title: Vice President


                                    ZML Investors, Inc.


                                    By:  /s/ Sheli Z. Rosenberg
                                         ---------------------------
                                         Name: Sheli Z. Rosenberg
                                         Title: Vice President


                                    ZML Investors II, Inc.


                                    By:  /s/ Sheli Z. Rosenberg
                                         ---------------------------
                                         Name: Sheli Z. Rosenberg
                                         Title: Vice President


                                    Zell/Merrill Lynch Real Estate Opportunity
                                         Partners III Trust


                                    By:  /s/ Donald J. Liebentritt
                                         ---------------------------
                                         Name: Donald J. Liebentritt
                                         Title: Vice President


                                    Zell/Merrill Lynch Real Estate Opportunity
                                         Partners IV Trust


                                    By:  /s/ Donald J. Liebentritt
                                         ---------------------------
                                         Name: Donald J. Liebentritt
                                         Title: Vice President



                                       21