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                                  EXHIBIT 10.7

                         PURCHASE AGREEMENT FOR THE LAND
                   IMMEDIATELY ADJACENT TO THE ADIC BUILDINGS

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                                                                     ADIC - Land

                               PURCHASE AGREEMENT

     THIS PURCHASE AGREEMENT ("Agreement") is made as of November 20, 2001, by
and between OPUS NORTHWEST, L.L.C., a Delaware limited liability company
("Seller") and WELLS CAPITAL, INC., a Georgia corporation ("Purchaser").

     In consideration of this Agreement, Seller and Purchaser agree as follows:

     1. Sale of Real Property. Seller agrees to sell to Purchaser, and Purchaser
agrees to buy from Seller, all of Seller's right, title and interest in and to
the following property:

        (a) Real Property. Fee simple interest in that certain parcel of real
     estate currently being part of the southern half of Lot 4A, Compark
     Filing No. 2 according to the recorded plat thereof recorded May 8, 2000,
     at Reception No. 20031092, Douglas County, Colorado, being approximately
     3.43 acres as more particularly depicted on Exhibit A hereto, which
                                                 ---------
     depiction is subject to verification by survey in accordance with Section
     3(b) below and platting pursuant to the provisions of Section 8 below (the
     "Land") together with all rights, privileges, easements, reversions, water
     rights, development rights, air rights, servitudes and appurtenances
     thereunto belonging or appertaining, and all right, title and interest of
     Seller, if any, in and to the streets, alleys and rights-of-way adjacent to
     the Land (collectively, the "Real Property").

     2. Purchase Price. The purchase price for the Real Property (the "Purchase
Price") will be $3.00 per square foot of "Net Area" (as defined below) included
in the Land. Upon recording of the "Amended Plat" (as defined in Section 8) and
completion of the "Survey" (as defined in Section 3(b) below) reflecting the
recording of the Lot Line Adjustment (as provided for in Section 8(a)), the
Purchase Price will be deemed adjusted to equal the amount per square foot set
forth above multiplied by the number of square feet of Net Area of the Land as
certified on the Survey. As used herein, "Net Area" means land area expressed in
square feet, excluding any land area lying within the dedicated public roads or
streets. The Purchase Price will be payable as follows:

        (a) Initial Earnest Money Deposit. Concurrently herewith, Purchaser
     shall deposit the sum of Twenty-Five Thousand and 00/100 Dollars
     ($25,000.00) with the escrow department of North American Title Company of
     Colorado ("Title Company") pursuant to an escrow agreement in substantially
     the form of Exhibit C attached hereto and made a part hereof (the "Escrow
                 ---------
     Agreement"). Such sum, together with any interest thereon less any
     investment fees related thereto, is sometimes hereinafter collectively
     referred to as the "Earnest Money." The Earnest Money shall be deposited in
     a federally insured interest-bearing money market account and disbursed
     according to the terms of this Agreement and the Escrow Agreement. All of
     the Earnest Money shall be credited against the Purchase Price and be paid
     to Seller at Closing.

        (b) Cash at Closing. The balance of the Purchase Price (after taking
     into account the payments made under (a) above, plus or minus prorations
     and other

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     adjustments, if any, shall be paid by Purchaser to Seller at Closing by
     wire transfer of immediately available funds.

     3.   Conditions Precedent to Closing. Purchaser's and Seller's respective
obligations to consummate the transaction contemplated by this Agreement shall
be subject to satisfaction or waiver of each of the following conditions
("Conditions Precedent") on or before November 30, 2001 ("Contingency Date"):

          (a) Underlying Purchase Agreement. Seller is a party to a certain
     Purchase and Sale Agreement dated August 24, 2001 (the "Underlying Purchase
     Agreement") by and between 470 Compark LLC ("Compark"), as seller, and
     Seller, as purchaser, pursuant to which Compark has agreed to sell and
     Seller has agreed to buy certain real property of which the Real Property
     is a part. The parties acknowledge that Seller's obligation to convey the
     Real Property is conditioned upon Seller successfully closing the purchase
     of the Real Property in accordance with the Underlying Purchase Agreement.
     Seller agrees to use its reasonable commercial efforts to complete the
     transaction contemplated by the Underlying Purchase Agreement on or before
     the Contingency Date.

          (b) Title/Survey. Seller has previously furnished or will furnish to
     Purchaser a current title commitment ("Commitment") for an owner's title
     policy issued by the Title Company showing title in Compark and including
     endorsements for zoning, mineral (Form 100.29) owner's comprehensive (Form
     100), covenants (Form 100.5), survey and access (with copies of all
     underlying title documents listed in the Commitment other than any
     financing documents encumbering the Real Property), which Commitment is in
     a nominal amount, but shall be increased to the Purchase Price at Closing,
     and will furnish to Purchaser at least ten business days prior to the
     Contingency Date, a ("Survey") for the Real Property prepared in accordance
     with the Minimum Standard Detail Requirements for Class A Land Title
     Surveys (jointly established by ALTA/ACSM, as revised in 1999) and
     certified to Seller, the Title Company, Purchaser, and Purchaser's lender.
     The Survey shall certify the description of the Land as subdivided pursuant
     to the Amended Plat (described in Section 8(a) below) and shall certify the
     Net Area of the Land for purposes of determining the Purchase Price. If the
     Survey discloses survey defects or if the Commitment shows exceptions
     (collectively, "Unpermitted Encumbrances") other than the matters set forth
     on Exhibit C attached hereto and made a part hereof (collectively,
        ---------
     "Permitted Encumbrances"), then Purchaser shall notify Seller, in writing,
     at least five business days prior to the Contingency Date, specifying the
     Unpermitted Encumbrances. In such event, prior to the Contingency Date,
     Purchaser shall have received adequate assurances in writing from Seller
     that the Unpermitted Encumbrances will be removed, satisfied, or cured on
     or before Closing, it being acknowledged by the parties hereto that the
     written commitment by the Title Company to delete such Unpermitted
     Encumbrance from the final title insurance policy to be issued by the Title
     Company shall constitute removal or cure of such Unpermitted Encumbrance
     for purposes hereof.

          (c) Tests. Seller has previously delivered or will deliver to
     Purchaser on or before November 17, 2001 true and correct copies of Permits
     and the environmental assessments or soils reports in Seller's possession
     or control with respect to the Real Property, for Purchaser's review and
     analysis. Seller shall allow Purchaser and

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     Purchaser's officers, employees, agents, attorneys, accountants, architects
     and engineers access to the Real Property and to the books and records in
     Seller's possession or control relating to the Real Property, without
     charge and at all reasonable times, for the purpose of making such
     inspections, tests and verifications (collectively, "Tests") as they shall
     deem reasonably necessary. On or before the Contingency Date, Purchaser
     shall be satisfied, in its sole and absolute discretion, with the results
     of the Tests. Purchaser shall pay all costs and expenses of the Tests and
     shall defend, indemnify and hold harmless Seller, and its agents, employees
     and contractors, and the Real Property, from and against any and all loss,
     cost, damage, liability, settlement, cause of action or threat thereof or
     expense (including, without limitation, reasonable attorneys' fees and
     costs) arising from or relating to the Tests. Purchaser shall cause any
     consultants retained by Purchaser and which shall enter upon the Real
     Property to name Seller and Seller's management agent as additional
     insureds on such consultants' policies of liability insurance. Purchaser
     shall promptly repair and restore any damage to the Real Property
     attributable to the conduct of the Tests, and shall promptly return the
     Real Property to substantially the same condition as existed prior to the
     conduct of the Tests. No Tests shall be conducted without Seller's approval
     as to the time and manner of such Tests, which approval shall not be
     unreasonably withheld or delayed. At Seller's sole option, any such Tests
     shall be performed in the presence of a representative of Seller. In the
     event Purchaser elects to terminate this Agreement as provided in this
     Section 3, or if this Agreement otherwise terminates as provided for
     hereunder for reasons other than default by Seller, then Purchaser shall
     promptly deliver to Seller copies of the written results of all Tests,
     including, without limitation, any environmental assessments prepared with
     respect to the Real Property; provided, however, if Purchaser and any
     consultants performing any of the Tests have entered into a written
     agreement prohibiting delivery of any Test results to any other party,
     Purchaser shall not be required so to deliver copies of the written results
     thereof. Anything in this Agreement to the contrary notwithstanding, the
     obligations of Purchaser under this Section 3(c) shall survive Closing and
     any termination of this Agreement; provided, however, that the indemnity by
     Purchaser in favor of Seller under this Section 3(c) shall survive only
     with respect to claims asserted in writing by Seller within one (1) year
     after the Closing or one (1) year after any termination of this Agreement.

     If any of the Conditions Precedent have not been satisfied on or before the
Contingency Date, or if Purchaser is not satisfied, in its sole and absolute
discretion, with any other aspect of the Real Property, then this Agreement may
be terminated, at Purchaser's sole option, by written notice from Purchaser to
Seller. Such notice of termination may be given at any time on or before the
Contingency Date. Except as otherwise provided herein, upon such termination,
neither party will have any further rights or obligations regarding this
Agreement or the Real Property, and the Earnest Money shall be returned to
Purchaser. Failure of Purchaser to give Seller notice of termination on or
before the Contingency Date shall constitute an irrevocable waiver by Purchaser
of the right of Purchaser to terminate this Agreement under this Section 3. All
the Conditions Precedent are specifically stated and agreed to be for the sole
and exclusive benefit of Purchaser, and Purchaser shall have the right
unilaterally to waive, in whole or in part, any Condition Precedent by written
notice to Seller.

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     4.   Covenants by Seller. Seller covenants and agrees with Purchaser that
from the date hereof until the Closing Date (as such term is defined in Section
9(a) hereof), Seller shall conduct its business involving the Real Property as
follows (except as specifically provided to the contrary herein):

          (a)  Transfers; Easements. Seller shall refrain from transferring any
     of the Real Property, or creating on the Real Property any easements,
     restrictions, liens, assessments or encumbrances without the express prior
     written consent of Purchaser, provided, however, that Seller may plat the
     Property as provided below.

          (b)  Contracts. Seller shall refrain from entering into or amending
     any contracts or other agreements regarding the Real Property (other than
     contracts in the ordinary course of business which are necessary to the
     closing of the transaction under the Underlying Purchase Agreement without
     the prior written consent of Purchaser, which consent shall not be
     unreasonably withheld or delayed.

     5.   Representations and Warranties by Seller.

          (a)  Representations and Warranties. Seller represents and warrants to
Purchaser as follows:

               (i)  Authority. Seller is a limited liability company duly
          organized and validly existing and in good standing under the laws of
          the State of Delaware and in good standing under the laws of the
          States of Minnesota and Colorado. Seller has the requisite power and
          authority to enter into and perform this Agreement and Seller's
          Closing Documents (as such term is defined in Section 10(a) hereof).
          This Agreement and Seller's Closing Documents have been duly
          authorized by all necessary action on the part of Seller and have been
          or will be duly executed and delivered by Seller. Seller's execution,
          delivery and performance of this Agreement and Seller's Closing
          Documents will not conflict with or result in a violation of Seller's
          organizational documents, or any judgment, order or decree of any
          court or arbiter, to which Seller is a party. This Agreement and
          Seller's Closing Documents (when signed) are valid and binding
          obligations of Seller, and are enforceable against Seller in
          accordance with their terms, subject to applicable bankruptcy,
          insolvency, reorganization, creditor's rights and other similar laws.

               (ii) Hazardous Substances. Seller shall make available to
          Purchaser in accordance with Section 3(c) hereof complete copies of
          all environmental reports and studies with respect to the Real
          Property conducted or received by Seller from any third party (the
          "Environmental Reports"). Except as disclosed by the Environmental
          Reports or any other environmental assessment obtained by Purchaser,
          to the best of Seller's knowledge, (A) the Real Property has never
          been used for the production, storage, deposit or disposal of
          hazardous substances in any reportable quantities under and in
          violation of applicable environmental laws; and (B) no above or below
          ground gas or fuel storage tank is or has been located at the Real
          Property. Seller has not received any written notice from any

                                       4

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         applicable governmental authority that any hazardous substances have
         been placed or located upon the Real Property in violation of
         applicable environmental laws.

              (iii)  FIRPTA. Seller is not a "foreign person," "foreign
         partnership," "foreign trust" or "foreign estate" as those terms are
         defined in Section 1445 of the Internal Revenue Code.

              (iv)   Proceedings. There is no action, litigation, condemnation
         or proceeding of any kind pending or, to the best knowledge of Seller,
         threatened against Seller or against any portion of the Real Property,
         which would have an adverse effect on the use or value of the Real
         Property or an adverse effect on the ability of Seller to perform its
         obligations under this Agreement.

              (v)    Condition of the Real Property. Seller has not received
         written notice from any governmental authority having jurisdiction over
         the Real Property of any violation of any applicable law, rule,
         regulation or code of any such governmental authority, which has not
         been cured or remedied and to the best of Seller's knowledge, no such
         violation exists.

              (vi)   Books and Records. To the best of Seller's knowledge, the
         books and records relating to the Real Property which have been made or
         will be made available to Purchaser by Seller accurately reflect the
         operation of the Real Property.

              (vii)  Special Assessments. Except as shown on any tax bills
         delivered to Purchaser and the Commitment, Seller has not received any
         notice, in writing, of any special assessments which affect the Real
         Property. Seller makes the following disclosure to Purchaser, which
         disclosure is required in certain circumstances by Colorado law:
         SPECIAL TAXING DISTRICTS MAY BE SUBJECT TO GENERAL OBLIGATION
         INDEBTEDNESS THAT IS PAID BY REVENUES PRODUCED FROM ANNUAL TAX LEVIES
         ON THE TAXABLE PROPERTY WITHIN SUCH DISTRICTS. PROPERTY OWNERS IN SUCH
         DISTRICTS MAY BE PLACED AT RISK FOR INCREASED MILL LEVIES AND EXCESSIVE
         TAX BURDENS TO SUPPORT THE SERVICING OF SUCH DEBT WHERE CIRCUMSTANCES
         ARISE RESULTING IN THE INABILITY OF SUCH A DISTRICT TO DISCHARGE SUCH
         INDEBTEDNESS WITHOUT SUCH AN INCREASE IN MILL LEVIES PURCHASERS SHOULD
         INVESTIGATE THE DEBT FINANCING REQUIREMENTS OF THE AUTHORIZED GENERAL
         OBLIGATION INDEBTEDNESS OF SUCH DISTRICTS, EXISTING MILL LEVIES OF SUCH
         DISTRICT SERVICING SUCH INDEBTEDNESS, AND THE POTENTIAL FOR AN INCREASE
         IN SUCH MILL LEVIES.

              (viii) No Other Agreements. Other than the Permitted Encumbrances,
         there are no leases, service contracts, management agreements, or other
         agreements or instruments in force and effect, oral or written, that
         grant to any

                                        5

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         person whomsoever or any entity whatsoever any right, title, interest
         or benefit in or to all or any part of the Real Property, any rights to
         acquire all or any part of the Real Property or any rights relating to
         the use, operation, management, maintenance, or repair of all or any
         part of the Real Property.

              (ix)   Certificates. Seller has heretofore provided Purchaser with
         complete and accurate copies of all Permits which are known by Seller
         to relate to the Real Property and which are in the possession or
         control of Seller.

              (x)    Bankruptcy. Seller is solvent and has not made a general
         assignment for the benefit of creditors nor been adjudicated a bankrupt
         or insolvent, nor has a receiver, liquidator, or trustee for any of
         Seller's properties (including the Real Property) been appointed or a
         petition filed by or against Seller for bankruptcy, reorganization, or
         arrangement pursuant to the Federal Bankruptcy Act or any similar
         Federal or state statute, or any proceeding instituted for the
         dissolution or liquidation of Seller.

              (xi)   No Roll Back Taxes. The Real Property has not been
          classified under any designation authorized by law to obtain a special
         low ad valorem tax rate or to receive a reduction, abatement, or
         deferment of ad valorem taxes which will result in additional, catch-up
         or roll-back ad valorem taxes in the future in order to recover the
         amounts previously reduced, abated or deferred.

         (b)  Seller's Knowledge. For purposes of this Agreement, the phrase
     "to the best of Seller's knowledge" or words of similar import shall mean
     the actual knowledge of John Shaw, Vice President, Marshall Burton, Senior
     Director of Development, and Scott L. Menefee, Director of Real Estate
     Development. Seller represents to Purchaser that such persons are the only
     officers or representatives of Seller having principal responsibility for
     the development, management, operation, leasing and sale of the Real
     Property.

         (c)  Representation and Warranty Becoming Untrue. In the event that,
     between the date of this Agreement and the Closing Date, Seller becomes
     aware that any of the foregoing representations and warranties of Seller is
     no longer true and correct, Seller shall promptly notify Purchaser thereof
     in writing. Seller covenants and agrees, within thirty (30) days (such
     thirty (30)-day period being sometimes hereinafter referred to as the
     "Warranty Cure Period"), to use reasonable efforts to cure any such then-
     incorrect representations and warranties, and the Closing shall be delayed
     in accordance with this Section 5(c) while Seller undertakes such efforts.
     If, after using reasonable efforts, Seller cannot effect such cure on or
     before the expiration of the Warranty Cure Period, Purchaser shall, within
     five (5) business days following expiration of the Warranty Cure Period,
     elect either (i) to terminate this Agreement (other than the rights and
     obligations of the parties that, by the express terms hereof, survive any
     termination of this Agreement), or (ii) to waive any such incorrect
     representations and warranties of Seller, and thereby release Seller from
     any and all liability or obligations with respect thereto, and to proceed
     hereunder, or (iii) if such representations and warranties of Seller are
     knowingly and intentionally breached by Seller, to exercise the remedies
     available to

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         Purchaser under Section 12(b) hereof. Failure of Purchaser to notify
         Seller within the aforesaid five (5)-business day period shall
         constitute Purchaser's irrevocable election under clause (ii) of the
         immediately preceding sentence. In the event that Purchaser terminates
         this Agreement as provided in clause (i) above, the Earnest Money shall
         be promptly returned to Purchaser.

         6.   Representations and Warranties by Purchaser. Purchaser represents
     and warrants to Seller as follows: (a) Purchaser is a Georgia corporation
     duly organized and validly existing and in good standing under the laws of
     the State of Georgia, and by the Closing Date, will be in good standing
     under the laws of Colorado as may be required in order for the Title
     Company to issue the Title Policy required hereunder; (b) Purchaser has the
     requisite power and authority to enter into this Agreement and Purchaser's
     Closing Documents (as such term is defined in Section 10(c) hereof); (c)
     this Agreement has been duly authorized by all necessary action on the part
     of Purchaser and this Agreement and Purchaser's Closing Documents have been
     or will be duly executed and delivered by Purchaser; (d) Purchaser's
     execution, delivery and performance of this Agreement and Purchaser's
     Closing Documents will not conflict with or result in violation of
     Purchaser's organizational documents, or any judgment, order or decree of
     any court or arbiter, to which Purchaser is a party; and (e) this Agreement
     and Purchaser's Closing Documents (when signed) are valid and binding
     obligations of Purchaser, and are enforceable against Purchaser in
     accordance with their terms, subject to applicable bankruptcy, insolvency,
     reorganization, creditor's rights and other similar laws.

         7.   Other Matters Related to Representations and Warranties of Seller
     and Purchaser. The respective representations and warranties of Seller and
     Purchaser contained in this Agreement shall survive Closing; provided,
     however, that (a) any cause of action that Purchaser may have against
     Seller by reason of a breach or default of any of Seller's representations
     and warranties set forth herein shall automatically expire on the date
     which is one (1) year after the Closing Date ("Warranty Expiration Date"),
     except that the same shall not expire as to any such breach or default as
     to which Purchaser has instituted litigation against Seller prior to the
     Warranty Expiration Date; (b) Seller's total liability for any breach or
     breaches of its representations and warranties set forth herein shall in no
     event exceed Seller's interest in the Real Property or the proceeds from
     the sale thereof, as the case may be; and (c) Seller shall have no
     liability whatsoever to Purchaser with respect to any breach or breaches by
     Seller of its representations and warranties set forth herein, if, prior to
     Closing, Purchaser obtains actual knowledge of a fact or circumstance, the
     existence of which would constitute a breach of Seller's representations
     and warranties set forth herein, unless such representations and warranties
     of Seller are knowingly and intentionally breached by Seller. Among other
     things, for purposes hereof, Purchaser shall be deemed to have actual
     knowledge of any fact or circumstance set forth in the estoppel
     certificates delivered to Purchaser and in any environmental assessments or
     engineering reports received by Purchaser. Seller's representations and
     warranties set forth herein shall be deemed automatically modified to the
     extent that any information contained in any estoppel certificates
     delivered to Purchaser prior to Closing or in any environmental assessments
     or engineering reports received by Purchaser is inconsistent with the
     matters which are the subject to such representations and warranties.

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         8.   Development Covenants. The parties agree as follows:

              (a)    Subdivision. Prior to Closing, Seller, at Purchaser's
                     -----------
     expense, will cause to be prepared, submitted and processed with the County
     through approval all necessary applications and submittals for, and prior
     to the Closing Seller will, at its expense, cause to be recorded in the
     County's real property records, an administrative lot line adjustment that
     will create the Land, having substantially the same size and configuration
     and as set forth for the Land on Exhibit A hereto (or with such changes
                                      ---------
     thereto as may be approved in writing by Purchaser), as a separate legally
     subdivided lot or as part of Lot 2, Compark Filing No. 2, Douglas County,
     Colorado (the "Lot Line Adjustment"). Immediately upon recording of the
     approved Lot Line Adjustment, the legal description of the Land made by
     reference to the subdivided lot created by the Lot Line Adjustment will be
     deemed to be the legal description of the Land for all purposes under this
     Agreement, including, without limitation, the calculation of the Purchase
     Price, the Preliminary Title Commitment, the Title Policy and Seller's deed
     to Purchaser. Both parties' obligations to close the purchase and sale of
     the Property hereunder are contingent upon the recording of the Lot Line
     Adjustment prior to Closing. If despite its good faith efforts Seller is
     unable to cause the Lot Line Adjustment to be recorded prior to the
     originally scheduled "Closing Date" (as defined in Section 9(a)), then the
     Closing Date will be extended as provided in Section 9(b) below subject to
     the other terms and conditions hereof.

         9.   Closing.

              (a)    Closing Date. The closing of the purchase and sale
     contemplated by this Agreement ("Closing") shall occur on or before
     December 21, 2001, or on such earlier or later date as Seller and Purchaser
     may mutually agree, subject to delays occasioned by operation of Sections
     3(a), 5(c), 8.1, 9(b), or 10(b) hereof ("Closing Date"), at the offices of
     Seller's attorneys, Briggs and Morgan, P.A., 2400 IDS Center, Minneapolis,
     MN 55402 or at such other location as Seller and Purchaser may mutually
     agree.

              (b)    Lot Line Adjustment/Extension. The parties acknowledge
     that, pursuant to Section 8(a), both parties' obligation to close are
     contingent upon the approval by Douglas County and recording of the Lot
     Line Adjustment. If the Lot Line Adjustment has not been approved and
     recorded by the original Closing Date set forth above or the date to which
     it may have been extended pursuant to this subsection (b), then the Closing
     Date will be extended to the later of (a) the seventh day after the Lot
     Line Adjustment is recorded; or (b) the date to which the Closing Date may
     be extended pursuant to this subsection (b). Seller will notify Purchaser
     if the Lot Line Adjustment will not be recorded prior to the then-scheduled
     Closing Date. Seller will also notify Purchaser not later than one day
     after the Lot Line Adjustment has been recorded and such notice will also
     specify the date (if applicable) to which the Closing Date has been
     extended pursuant to this subsection (b). If, despite Seller's efforts to
     cause the same to be approved and recorded, the Lot Line Adjustment has not
     been approved and recorded by February 28, 2002, then either party may
     terminate this Agreement by notice to the other, so long as such notice is
     given before Seller's notice to Purchaser that the Lot Line Adjustment has
     been recorded. Upon timely delivery of any such notice of termination, this
     Agreement will terminate, the Earnest Money will be returned to Purchaser
     and both parties will be

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         relieved of any further obligations hereunder, except for those
         obligations which expressly survive any termination hereof.

              (c)    Purchaser's Closing Conditions Precedent. Purchaser's
         obligation to consummate the transaction contemplated by this Agreement
         shall be subject to satisfaction or waiver of each of the following
         conditions ("Purchaser's Closing Conditions Precedent"); provided,
         however, that Purchaser shall have the unilateral right to waive any
         Purchaser's Closing Condition Precedent, in whole or in part, by
         written notice to Seller:

                     (i)   The representations and warranties of Seller set
              forth in Section 5(a) hereof shall be, in all material respects,
              true and complete as of the Closing Date.

                     (ii)  Seller shall have performed all of the obligations
              required to be performed by Seller under this Agreement, as and
              when required by this Agreement, in all material respects.

                     (iii) Seller shall deliver to Purchaser the Survey.

                     (iv)  Seller shall have closed the sale to Purchaser of the
              Subject Property described in that certain Purchase Agreement
              dated October 25, 2001 by and between Seller and Purchaser (the
              "ADIC Building Purchase Agreement") in accordance with the terms
              thereof.

              (d)    Seller's Conditions Precedent. Seller's obligation to
         consummate the transaction contemplated by this Agreement shall be
         subject to satisfaction or waiver of each of the following conditions
         ("Seller's Closing Conditions Precedent"); provided, however, that
         Seller shall have the unilateral right to waive any Seller's Closing
         Condition Precedent, in whole or in part, by written notice to
         Purchaser:

                     (i)   The representations and warranties of Purchaser set
              forth in Section 6 hereof shall be, in all material respects, true
              and complete.

                     (ii)  Purchaser shall have performed all of the obligations
              required to be performed by Purchaser under this Agreement, as and
              when required by this Agreement, in all material respects.

                     (iii) Purchaser shall have closed the purchase from Seller
              of the subject Property described in the ADIC Building Purchase
              Agreement in accordance with the terms thereof.

                     (iv)  Seller shall have closed the purchase of the Land
              from Compark pursuant to the Underlying Purchase Agreement.

              (e)    Failure of Condition Precedent. In the event that
         Purchaser's Closing Condition Precedent or Seller's Closing Conditions
         Precedent, as the case may be, have not been satisfied or waived as of
         the scheduled Closing Date as the same may be

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          extended as permitted above, and provided the failure to satisfy or
          waive any such condition is not attributable to a breach or default of
          this Agreement by Seller or Purchaser, as the case may be, this
          Agreement shall terminate (other than the obligations of the parties
          that, by the express terms hereof, survive any such termination) and
          the Earnest Money shall be returned to the Purchaser.

          10. Closing Deliveries.

              (a) Seller's Closing Documents. On the Closing Date, Seller shall
          execute and/or deliver to Purchaser or cause to be executed and/or
          delivered the following (collectively, "Seller's Closing Documents"):

                  (i)   Deed. A Special Warranty Deed conveying the Real
               Property to Purchaser, free and clear of all encumbrances, except
               the Permitted Encumbrances, in the form set forth in Exhibit D
                                                                    ---------
               attached hereto and made a part hereof (the "Deed").

                  (ii)  Seller's Affidavit. An Affidavit of Seller indicating
               that on the Closing Date, to the best of Seller's knowledge,
               there are no outstanding, unsatisfied judgments, tax liens (other
               than the lien of real estate taxes not yet due and payable) or
               bankruptcies against or involving Seller or the Real Property;
               and that, to the best of Seller's knowledge, there are no other
               unrecorded interests in the Real Property other than the Lease.
               Such Affidavit shall be in such form and shall contain such
               averments as may be reasonably required by the Title Company in
               order for the Title Company to issue to Purchaser its owner's
               policy of title insurance without exception for rights of parties
               in possession (other than the rights of the Tenant under the
               Lease, as tenant only) and without exception for filed or unfiled
               mechanics' and materialmen's liens.

                  (iii) FIRPTA Affidavit. A non-foreign affidavit properly
               containing such information as is required by Section 1445(b)(2)
               of the Internal Revenue Code and the regulations promulgated
               thereunder.

                  (iv)  Colorado Form DR-1083. A Colorado Form DR-1083, in
               form required by law and signed by Seller, concerning the
               transaction contemplated by this Agreement.

                  (v)   Title Documents. Such affidavits of Seller or other
               documents as may be reasonably required by the Title Company in
               order to record the Deed and issue the title insurance policy
               required by this Agreement.

                  (vi)  Tax Reporting Designation. A Designation of Person
               Responsible for Tax Reporting under Internal Revenue Code Section
               6045 in the form of Exhibit E attached hereto and made a part
                                   ---------
               hereof designating the Title Company as the party responsible for
               making returns required under Internal Revenue Code Section 6405.

                                       10

<PAGE>

          (b)  Title Policy. At Closing, Seller shall cause the Title Company to
     deliver to Purchaser its owner's title insurance policy required by this
     Agreement. Seller hereby agrees that Seller shall remove, satisfy or cure
     at or prior to the Closing, any Unpermitted Encumbrances created by Seller
     after the effective date of this Agreement in violation of this Agreement
     or any Unpermitted Encumbrances consisting of taxes and installments of
     special assessments (except for taxes which are not yet due or payable
     which shall be prorated between Seller and Purchaser and installments of
     special assessments as provided in Section 10(a) below), mortgages,
     mechanic's or materialmen's liens or other such monetary encumbrances. In
     the event that Seller shall fail, on or before the date of Closing, to
     remove, satisfy or cure any Unpermitted Encumbrances that Seller is
     obligated hereunder to remove, satisfy or cure or as to which Seller gave
     assurance to Purchaser that Seller would remove, satisfy or cure as
     provided in Section 3(b) above or that Seller created after the Effective
     Date of this Agreement in violation of this Agreement, (i) Purchaser may
     terminate this Agreement by written notice to Seller and Title Company, in
     which even the Earnest Money shall be immediately refunded to Purchaser,
     (ii) Purchaser may remove, cure or cause the Title Company to endorse over
     such Unpermitted Encumbrance, in which event the Purchase Price payable
     pursuant to Section 2 hereof shall be reduced by an amount equal to the
     actual cost and expense incurred by Purchaser in connection with the
     removing, curing or endorsing over of such Unpermitted Encumbrance, or
     (iii) Purchaser may accept title to the Real Property subject to such
     Unpermitted Encumbrances, or (iv) any combination of items (ii) and (iii).
     In the event Purchaser elects to remove, cure or cause the Title Company to
     endorse over any such Unpermitted Encumbrances pursuant to item (ii) above,
     Purchaser at its option, upon giving notice to Seller, may extend the date
     of Closing until the curing of such Unpermitted Encumbrances or fifteen
     (15) days from and after the previously scheduled date of Closing,
     whichever shall first occur. If any defect or objection shall not have been
     removed, cured or endorsed over within such period, Purchaser may exercise
     its option under either item (i), (ii) or (iii) hereof.

          (c)  Purchaser's Closing Documents. On the Closing Date, Purchaser
     shall execute and/or deliver or cause to be executed and/or delivered to
     Seller the following (collectively, "Purchaser's Closing Documents"):

               (i)   Purchase Price. The cash portion of Purchase Price, plus or
          minus prorations and other adjustments, if any, by wire transfer of
          immediately available funds.

               (ii)  Transfer Declaration. A real property transfer declaration,
          in form required by law and signed by Purchaser, concerning the
          transaction contemplated by this Agreement.

               (iii) Title Documents. Such affidavits of Purchaser other
          documents as may be reasonably required by the Title Company in order
          to record the Deed and issue the title insurance policy required by
          this Agreement.

          (d)  Purchaser's and Seller's Closing Documents. On the Closing Date,
     Seller and Purchaser shall jointly execute and deliver the following:

                                       11



<PAGE>

                    (i)  Closing Statement. A closing statement in form and
               substance reasonably acceptable to both Seller and Purchaser, and
               consistent with the terms, provisions and conditions of this
               Agreement.

                    (ii) Miscellaneous. Such other documents, instruments and
               affidavits as shall be reasonably necessary to consummate the
               transaction contemplated by this Agreement, including, without
               limitation, affidavits identifying any brokers involved as the
               only persons entitled to a brokerage or similar commission in
               connection with consummation of the transaction contemplated
               hereby.

          11.  Adjustment and Prorations. At Closing, Seller and Purchaser shall
make all adjustments and apportion all expenses with respect to the Real
Property, including, without limitation, the following:

               (a)  Ad Valorem Taxes. All real estate taxes attributable to the
          Property will be prorated as of the date immediately preceding the
          Closing Date (the "Proration Date"). Seller will pay all such taxes
          attributable to any period prior to the Closing Date. If the
          applicable tax rate and assessments for the Property have not been
          established for the year in which Closing occurs, the proration of
          real estate and/or personal property taxes as the case may be, will be
          based upon the rate and assessments for the preceding year with such
          proration to be adjusted in cash between Seller and Purchaser promptly
          after presentation of written evidence that the actual taxes payable
          for the year in which Closing occurs differ from the amounts used for
          proration purposes at Closing.

               (b)  Title Insurance/Survey. Seller shall pay for the cost of the
          base owner's title insurance policy required under this Agreement and
          the Survey. Purchaser shall pay for the cost of any and all
          endorsements to the owner's title insurance policy which Purchaser is
          able to obtain from the Title Company, and all costs of any lender's
          title insurance policy.

               (c)  Closing Fee. Seller and Purchaser will each pay one-half of
          any reasonable and customary closing fee by the Title Company.

               (d)  Recording Costs. Seller shall pay the cost of recording all
          documents necessary to place record title in the condition required by
          this Agreement other than the cost of recording the Deed which shall
          be paid by Purchaser.

               (e)  Attorney's Fees. Each of the parties shall pay its own
          attorneys' fees, except that a party defaulting under this Agreement
          or any closing document shall pay the reasonable attorneys' fees and
          court costs incurred by the nondefaulting party to enforce
          successfully its rights regarding such default.

               (f)  Platting Expenses. Purchaser shall pay to Seller all costs
          of preparing and filing the Plat as provided in Section 8(a) above.

               (g)  Other Costs. All other costs shall be allocated in
          accordance with the customs prevailing in similar transactions in the
          greater metropolitan Denver area.

                                       12



<PAGE>

          The obligations of the parties under this Section 10 shall survive the
     Closing and delivery of the Deed.

          12.  Default.

               (a) If Purchaser defaults in its obligation to consummate this
          Agreement, Seller shall be entitled, at Seller's option, to terminate
          this Agreement, and the Earnest Money shall be forfeited to Seller, as
          Seller's sole and exclusive remedy; provided, however, that Seller
          shall also have the right to sue for or otherwise recover actual
          damages as a result of Purchaser's failure to perform Purchaser's
          indemnity obligations herein.

               (b) If Seller defaults in its obligations under this Agreement or
          knowingly and intentionally breaches its representations and
          warranties hereunder, Purchaser shall be entitled either (i) to
          terminate this Agreement and have the Earnest Money returned as
          Purchaser's sole and exclusive remedy, or (ii) to enforce specific
          performance of the terms and provisions of this Agreement; provided,
          however, that if Purchaser elects to terminate this Agreement and have
          the Earnest Money returned, Seller agrees to pay the actual
          out-of-pocket expenses incurred by Purchaser (not to exceed $10,000)
          in connection with Purchaser's proposed acquisition of the Property.

          13.  Condemnation. If, prior to the Closing Date, eminent domain
     proceedings are commenced against all or any part of the Real Property, or
     if the Real Property is subjected to a bona fide threat of eminent domain,
     or if Seller has received notice that any such eminent domain proceedings
     are contemplated, Seller shall immediately give notice to Purchaser of such
     fact and, at Purchaser's option (to be exercised within thirty (30) days
     after Seller's notice), this Agreement shall terminate. In the event of any
     such termination, neither party will have further obligations under this
     Agreement (other than the obligations of the parties that, by the express
     terms hereof, survive any such termination), and the Earnest Money shall be
     refunded to Purchaser. If Purchaser fails to elect to terminate (in the
     manner provided in this Section 13), then there shall be no reduction in
     the Purchase Price, and Seller shall assign to Purchaser at the Closing
     Date all of Seller's right, title and interest in and to any award made or
     to be made in the condemnation proceedings. Prior to the Closing Date,
     Seller shall not designate counsel, appear in, or otherwise act with
     respect to the condemnation proceedings without Purchaser's prior written
     consent, which consent shall not be unreasonably withheld or delayed;
     provided, however, that if any action is necessary with respect to such
     proceeding to avoid any forfeiture or material prejudice, Seller shall be
     entitled to take such action as and to the extent necessary without
     obtaining Purchaser's prior written consent.

          14.  Broker's Commission. Seller represents and warrants to Purchaser
     that in connection with the transaction contemplated hereby, no third party
     broker or finder has been engaged or consulted by Seller or is entitled to
     compensation or commission in connection herewith. Seller shall defend,
     indemnify and hold harmless Purchaser from and against any and all claims
     of brokers, finders or any like third party claiming any right to
     commission or compensation by or through acts of Seller in connection
     herewith, other than Purchaser's Broker (defined below). Purchaser
     represents and warrants to Seller that in connection with the transaction
     contemplated hereby, no third party broker or finder has been engaged or
     consulted

                                       13

<PAGE>

by Purchaser or is entitled to compensation or commission in connection
herewith. Purchaser shall defend, indemnify and hold harmless Seller from and
against any and all claims of brokers, finders or any like party claiming any
right to commission or compensation by or through acts of Purchaser in
connection herewith. The indemnity obligations hereunder shall include, without
limitation, all damages, losses, risks, liabilities and expenses (including,
without limitation, reasonable attorneys' fees and costs) arising from and
related to matters being indemnified hereunder. Neither Purchaser's Broker nor
any other broker, finder or like party shall be entitled to rely (as a
third-party beneficiary or otherwise) on the provisions herein in claiming any
right to commission or compensation or otherwise. The obligations of the parties
under this Section 14 shall survive the Closing or any termination of this
Agreement.

     15.  Mutual Indemnification. Seller and Purchaser agree to indemnify each
other against, and hold each other harmless from all liabilities (including,
without limitation, reasonable attorneys' fees in defending against claims)
arising out of the ownership, operation or maintenance of the Real Property for
their respective periods of ownership; provided, however, that nothing herein
shall diminish the defense, indemnify and hold harmless obligations of Purchaser
set forth in Section 3(b) hereof with respect to matters arising from or related
to the Tests. If and to the extent that the indemnified party has insurance
coverage, or the right to make claim against any third party for any amount to
be indemnified against as set forth above, the indemnified party will, upon full
performance by the indemnifying party of its indemnification obligations, assign
such rights to the indemnifying party. If such rights are not assignable, the
indemnified party will diligently pursue such rights by appropriate legal action
or proceeding and assign the recovery and/or right of recovery to the
indemnifying party to the extent of the indemnification payment made by such
party. The provisions of this Section 15 shall survive Closing and execution and
delivery of the Deed.

     16.  Assignment. Purchaser may not assign its rights under this Agreement
without the prior written consent of Seller; provided, however, that Purchaser
may assign its rights under this Agreement to Wells Operating Partnership, L.P.,
a Delaware limited partnership ("WLP") or Wells Real Estate Investment Trust,
Inc., a Maryland corporation ("Wells REIT") or Wells Development Corporation, a
Georgia corporation ("WDC") or any trust, corporation, partnership or limited
liability company controlling, controlled by or under common control with
Purchaser, WLP, Wells REIT, WDC or any partnership having Purchaser, WLP, Wells
REIT or WDC or any entity controlled by Purchaser, WLP, Wells Reit or WDC as a
direct or indirect general partner. For purposes hereof, "control" shall mean
ownership (directly or indirectly) of 51% or more of the voting or other
comparable ownership interest of any such trust, corporation, partnership or
limited liability company. Any assignment shall be subject to all the
provisions, terms, covenants and conditions of this Agreement, and the assignor
shall, in any event, continue to be and remain liable under this Agreement, as
it may be amended from time to time, as a principal and not as a surety without
notice to such assignor. Any such assignment and assumption shall be evidenced
by a written agreement in form and substance reasonably acceptable to Seller.

     17.  Notices. Any notice or other communication in connection with this
Agreement shall be in writing and shall be sent by United States certified mail,
return receipt requested, postage prepaid, by nationally recognized overnight
courier guarantee next day delivery, by telecopy or facsimile transmission, or
by personal delivery, properly addressed as follows:

                                       14

<PAGE>

         If to Seller:          Opus Northwest, L.L.C.
                                1855 Blake Street
                                Suite 200
                                Denver, CO 80202
                                Attn: John Shaw, Vice President
                                Facsimile No.: (303) 297-3300

         With a copy to:        Opus L.L.C. Legal Department
                                10350 Bren Road West
                                Minnetonka, MN 55343
                                Attn:  Brad Osmundson
                                Facsimile No.: (952) 656-4814

         And a copy to:         Briggs and Morgan, P.A.
                                2400 IDS Center
                                Minneapolis, MN 55402
                                Attn: Charles R. Haynor, Esq.
                                Facsimile No.: (612) 334-8650

         If to Purchaser:       Wells Capital, Inc.
                                6200 The Corners Parkway
                                Suite 250
                                Norcross, GA 30092
                                Attn: Michael C. Berndt
                                Facsimile No.: (770) 200-8199

         With a copy to:        O'Callaghan & Stumm LLP
                                127 Peachtree Street NE, Suite 1330
                                Atlanta, GA 30303
                                Attn: William L. O'Callaghan, Esq.
                                Facsimile No.: (404) 522-3080

All notices shall be deemed given three (3) business days following deposit in
the United States mail with respect to certified or registered letters, one (1)
business day following deposit if delivered to an overnight courier guaranteeing
next day delivery and on the same day if sent by personal delivery or by
telecopy or facsimile transmission (with proof of transmission). Attorneys for
each party shall be authorized to give notices for each such party. Any party
may change its address for the service of notice by giving written notice of
such change to the other party, in any manner above specified.

     18. Captions. The section headings or captions appearing in this Agreement
are for convenience only, are not a part of this Agreement, and are not to be
considered in interpreting this Agreement.

     19. Entire Agreement; Modification. This Agreement constitutes the entire
agreement between the parties with respect to the subject matter herein
contained, and all prior negotiations, discussions, writings and agreements
between the parties with respect to the subject

                                       15

<PAGE>

matter herein contained are superseded and of no further force and effect. No
covenant, term or condition of this Agreement shall be deemed to have been
waived by either party, unless such waiver is in writing signed by the party
charged with such waiver.

     20. Binding Effect. This Agreement shall be binding upon and inure to the
benefit of the parties hereto and their respective successors and permitted
assigns.

     21. Controlling Law. This Agreement shall be governed by and construed in
accordance with the laws of the State of Colorado.

     22. Severability. The unenforceability or invalidity of any provisions
hereof shall not render any other provision herein contained unenforceable or
invalid.

     23. "As Is" Sale. Purchaser acknowledges that except as set forth in this
Agreement and in Seller's Closing Documents (which term "Seller's Closing
Documents" includes the documents referred to in Section 9(d) above), (a)
neither Seller, nor any principal, agent, attorney, employee, broker, or other
representative of Seller, has made any representation or warranty of any kind
whatsoever, either express or implied, with respect to the Real Property or any
matter related thereto; (b) Purchaser is not relying on any warranty,
representation, or covenant, express or implied, with respect to the condition
of the Real Property; and (c) Purchaser is acquiring the Real Property in its
"AS-IS" CONDITION WITH ALL FAULTS. In particular, but without limitation, except
as set forth in this Agreement and the Seller's Closing Documents, Seller makes
no representations or warranties with respect to the use, condition, occupation
or management of the Real Property, compliance of the Real Property with
applicable statutes, laws, codes, ordinances, regulations or requirements or
compliance of the Real Property with covenants, conditions, and restrictions,
whether or not of record.

     24. Time of Essence. Time is of the essence of this Agreement.

     25. Counterparts. This Agreement may be executed in any number of
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

     26. Exhibits. The following exhibits are made a part hereof, with the same
force and effect as if specifically set forth herein:

         Exhibit A -   Depiction of Land
         Exhibit B -   Form of Earnest Money Escrow Agreement
         Exhibit C -   Permitted Encumbrances
         Exhibit D -   Form of Special Warranty Deed
         Exhibit E -   Designation of Person Responsible for Tax Reporting

                                       16

<PAGE>

     IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of
the day and year first above written.

PURCHASER:                               SELLER:

WELLS CAPITAL, INC.,                     OPUS NORTHWEST, L.L.C.
a Georgia corporation                    a Delaware limited liability company

By: /s/ Douglas P. Williams              By:   /s/ John M. Shaw
   -------------------------------          ------------------------------------

Its:  Douglas P. Williams                Its: V.P./GENERAL MANAGER
    ------------------------------           -----------------------------------
      Senior Vice President

                                       17

<PAGE>

                                    EXHIBIT A

                                Depiction of Land

                                      A-1

<PAGE>

                                    EXHIBIT A

                                  Real Property

                                     [MAP]

<PAGE>

                                    EXHIBIT B

                     Form of Earnest Money Escrow Agreement

     THIS EARNEST MONEY ESCROW AGREEMENT ("Agreement") is made as of November
__, 2001, by and among OPUS NORTHWEST, L.L.C., a Delaware limited liability
company ("Seller"), WELLS CAPITAL, INC., a Georgia corporation ("Purchaser"),
and North American Title Company of Colorado, a Colorado corporation ("Escrow
Agent").

                                    RECITALS:

     A. By that certain Purchase Agreement dated as of November ___, 2001
"Purchase Agreement"), between Seller and Purchaser, Seller has agreed to sell
to Purchaser and Purchaser has agreed to purchase from Seller all of Seller's
right, title and interest in and to the Real Property, upon and subject to the
terms and provisions set forth in the Purchase Agreement.

     B. Seller and Purchaser desire that Escrow Agent act as escrowee to
receive, hold and disburse funds in the manner hereinafter set forth.

     C. Unless otherwise provided herein, all capitalized words and terms used
herein shall have the same meanings ascribed to such words and terms as in the
Purchase Agreement.

     NOW THEREFORE, in consideration of the mutual covenants and agreements
hereinafter set forth and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto hereby agree as
follows:

     1. Purchaser shall deposit with Escrow Agent the sum of Twenty Five
Thousand and 00/100 ($25,000) as earnest money ("Earnest Money"). The Earnest
Money, upon receipt by Escrow Agent, shall be invested in Escrow Agent's
customary money market account. Purchaser shall be entitled to the interest
accrued on the Earnest Money and the Earnest Money shall include such accrued
interest. Escrow Agent shall acknowledge to Seller, in writing, receipt of the
Earnest Money when it is delivered to Escrow Agent.

     2. Purchaser's Tax Identification Number is 58-1565532.

     3. Escrow Agent shall not be responsible for any penalties or loss of
interest or any delays in withdrawing funds which may be incurred upon
withdrawal of the Earnest Money in accordance with instructions given hereunder
except to the extent attributable to Escrow Agent's negligence.

     4. In the event Escrow Agent receives written notice of default,
non-performance, dispute or exercise of right under the Purchase Agreement from
Seller or Purchaser accompanied by a demand for delivery to such party of the
Earnest Money, Escrow Agent is immediately to give written notice to the other
party of such claim and accompanying demand. In the event the other party fails
to dispute or object to such claim and demand within ten (10) business days from
the date of Escrow Agent's written notice, Escrow Agent is authorized to deliver
the Earnest Money to the party making such claim and demand. In the event the
other party disputes or objects to the aforesaid claim and demand within the
10-business day period prescribed

                                     B-1

<PAGE>

herein, Escrow Agent is not to deliver the Earnest Money deposited hereunder
without receipt of a mutual agreement of the parties, in writing, or appropriate
court order. Subject to the foregoing, this Agreement shall at all times be
subject to the joint order of Seller and Purchaser and upon such joint order
Escrow Agent shall deliver the Earnest Money as instructed by such joint order.

     5. Seller and Purchaser shall each be responsible for payment of one-half
of any escrow fee hereunder. Purchaser shall be responsible for payment of any
investment fee.

     6. Any notice or other communication in connection with this Agreement
shall be in writing and shall be sent by United States certified mail, return
receipt requested, postage prepaid, by nationally recognized overnight courier
guarantee next day delivery, by telecopy or facsimile transmission, or by
personal delivery, properly addressed as follows:

           If to Seller:          Opus Northwest, L.L.C.
                                  1855 Blake Street
                                  Suite 200
                                  Denver, CO 80202
                                  Attn:  John Shaw, Vice President
                                  Facsimile No.: (303) 297-3300

           With a copy to:        Opus L.L.C. Legal Department
                                  10350 Bren Road West
                                  Minnetonka, MN 55343
                                  Attn:  Brad Osmundson
                                  Facsimile No.: (952) 656-4814

           And a copy to:         Briggs and Morgan, P.A.
                                  2400 IDS Center
                                  Minneapolis, MN 55402
                                  Attn:  Charles R. Haynor, Esq.
                                  Facsimile No.: (612) 334-8650

           If to Purchaser:       Wells Capital, Inc.
                                  6200 The Corners Parkway
                                  Suite 250
                                  Norcross, GA 30092
                                  Attn:  Michael C. Berndt
                                  Facsimile No.:  (770) 200-8199

           With a copy to:        O'Callaghan & Stumm LLP
                                  127 Peachtree Street NE, Suite 1330
                                  Alanta, GA 30303
                                  Attn:  William L. O'Callaghan, Esq.
                                  Facsimile No.: (404) 522-3080

                                      B-2


<PAGE>

               If to Escrow Agent:      North American Title Company of Colorado
                                        929 Broadway
                                        Denver, CO 80203
                                        Attn:  Valena Mulhern
                                        Facsimile No.: (303) 352-2101

All notices shall be deemed given three (3) business days following deposit in
the United States mail with respect to certified or registered letters, one (1)
business day following deposit if delivered to an overnight courier guaranteeing
next day delivery and on the next business day if sent by personal delivery or
by telecopy or facsimile transmission (with proof of transmission). Attorneys
for each party shall be authorized to give notices for each such party. Any
party may change its address for the service of notice by giving written notice
of such change to the other party, in any manner above specified.

     7. This Agreement shall be binding upon and inure to the benefit of the
parties hereto and their respective successors and permitted assigns under the
Purchase Agreement.

     8. This Agreement shall be governed by and construed in accordance with the
laws of the State of Colorado. In the event that any provision hereof shall be
deemed illegal or unenforceable, said provision shall be severed herefrom and
the remainder of this Agreement shall be enforced in accordance with the
intentions of the parties as herein expressed.

     9. This Agreement may not be amended or altered except by an instrument in
writing executed by all the parties hereto.

     10.Except as to deposits of funds for which Escrowee has received express
written direction concerning investment or other handling, the parties hereto
agree that the Escrow Agent shall invest the Earnest Money in Escrow Agent's
customary federally insured money market account.

     11.If any party shall bring suit against the other to enforce the terms of
this Agreement, the losing party shall pay to the prevailing party the
prevailing party's costs and expenses (including, without limitation, reasonable
attorneys' fees and costs) incurred in enforcing this Agreement.

                                      B-3

<PAGE>

        IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the day and year first above written.

PURCHASER:                                    SELLER:
WELLS CAPITAL, INC.,                          OPUS NORTHWEST, L.L.C.

By:______________________________             By:_______________________________
   Its:__________________________                Its:___________________________


ESCROW AGENT:
NORTH AMERICAN TITLE
COMPANY OF COLORADO

By:______________________________
   Its:__________________________

                                      B-4






<PAGE>

                                    EXHIBIT C

                             Permitted Encumbrances

     1.  Taxes and assessments which are a lien, but which are not yet billed,
or are billed but are not yet delinquent.

     2.  Any laws, regulations or ordinances (including, but not limited to,
zoning, building and environmental matters) as to the use, occupancy,
subdivision or improvement of the Real Property adopted or imposed by any
governmental agency.

     3.  Acts done or suffered by, through or under, or judgments against,
Purchaser.

     4.  Such other covenants, conditions, restrictions, easements or other
title matters and exceptions as may be consented to by Purchaser in a separate
writing.

     5.  Any and all water rights or claims or title to water in, on or under
the land.

     6.  The right of the proprietor of a vein or lode to extract or remove his
ore, should the same be found to penetrate or intersect the premises thereby
granted as reserved in the United States Patent recorded December 15, 1897 in
Book X at Page 323, and any and all assignments thereof or interests therein.

     7.  The right of the proprietor of a vein or lode to extract or remove his
ore, should the same be found to penetrate or intersect the premises thereby
granted as reserved in the United States Patent recorded October 28, 1909 in
Book X at Page 524, and any and all assignments thereof or interests therein.

     8.  The covenants, conditions and restrictions imposed on the property by
inclusion within the Arapahoe County Airport Influence Area, as disclosed by the
instrument recorded February 8, 1983 in Book 465 at Page 324.

     9.  Powers of the Cherry Creek Basin Authority as set forth in Article
25-8.5-111 in that instrument recorded May 6, 1988 in Book 790 at Page 718.

     10. The effect of the inclusion of the subject property in the E-470
Business Metropolitan District, as disclosed by the instrument recorded February
25, 1998 in Book 1515 at Page 1832.

     11. Covenants, conditions and restrictions as shown on the Compark Planned
Development recorded September 21, 1998 at Reception No. 9875113 and a
Resolution Approving Compark PD Rezoning and Major Amendment recorded June 16,
1999 in Book 1721 at Page 1047.

     12. Easements, notes, terms, conditions, provisions, agreements and
obligations as shown on the plat of Compark Filing No. 2 recorded May 8, 2000 at
Reception No. 200031092.

                                       C-1



<PAGE>

     13. The following matters as set forth on ALTA/ACSM Land Title Survey by
Carroll & Lange, Inc., dated June 22, 2000 and last revised September 28, 2000,
Job No. 2181 as follows:

         (a) Sanitary sewer line runs from the Southeast corner of the property
     outside of a designated easement area.

     14. An easement for utility lines and incidental purposes granted to Public
Service Company of Colorado by the instrument recorded September 11, 2000 in
Book 1893 at Page 545.

     15. An easement for storm drainage facilities and incidental purposes
granted to The Board of County Commissioners of the County of Douglas by the
instrument recorded January 10, 2001 in Book 1947 at Page 263.

     16. Matters shown on the Survey, not objected to by Purchaser pursuant to
Section 3(a) of the Purchase Agreement.

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