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          SEVENTH MODIFICATION OF MASTER CONSTRUCTION LOAN AGREEMENT

         THIS SEVENTH MODIFICATION, dated and effective as of September 30,
1999, is made and entered into by and between TRAMMELL CROW BTS, INC., a
Delaware corporation having a notice address of 7535 East Hampden Avenue,
Suite 650, Denver, Colorado 80231-4845 ("Developer"), and KEYBANK NATIONAL
ASSOCIATION, a national banking association having a notice address of 10
West Market Street, 9th Floor, Indianapolis, Indiana 46204 ("Bank").

                                   RECITALS:

         A. Developer and Bank entered into that certain Master Construction
Loan Agreement, dated August 4, 1997, as modified by that certain First
Modification of Master Construction Loan Agreement between Developer and
Bank, dated September 15, 1997, as modified by that certain Second
Modification of Master Construction Loan Agreement between Developer and
Bank, dated May 12, 1998, as modified by that certain Third Modification of
Master Construction Loan Agreement between Developer and Bank, dated June 9,
1998, as modified by that certain Fourth Modification of Master Construction
Loan Agreement between Developer and Bank, dated December 30, 1998, as
modified by that certain Fifth Modification of Master Construction Loan
Agreement between Developer and Bank, dated April 23, 1999, and as modified
by that certain Sixth Modification of Master Construction Loan Agreement
between Developer and Bank, dated May 31, 1999 (collectively, the "Loan
Agreement").

         B. The parties hereto desire to further modify the Loan Agreement in
accordance with the terms and conditions set forth herein.

                                    AGREEMENT

         NOW THEREFORE, for and in consideration of the foregoing and for
other good and valuable consideration, the receipt and sufficiency of which
are hereby acknowledged the parties hereto agree as follows:

         1. DEFINITIONS OF THE LOAN AGREEMENT. Paragraph 1.01 of the Loan
Agreement is hereby modified by substituting the following in lieu of the
existing like defined term:

                  "Loan" shall mean the aggregate amount of the Project Loans
         approved by Bank pursuant to this Agreement, which amount shall in no
         event exceed the principal sum of Thirty Million Dollars ($30,000,000)
         outstanding at any time.

                  "Project Loan Commitment Expiration Date" shall mean
         July 31, 2000.

         2. SECTION 2.01 OF THE LOAN AGREEMENT. Section 2.01 of the Loan
Agreement is hereby modified in its entirety to read as follows:


            2.01. PROJECT LOAN. Subject to the terms and conditions hereof, and
         relying upon the representations and warranties herein set forth, the
         Bank agrees to make

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         Project Loans to the Borrower(s) from time to time in an aggregate
         principal amount not to exceed Thirty Million Dollars ($30,000,000)
         outstanding at any time. In no event shall the Bank be obligated to
         make a Project Loan in respect of a Project for which there is not then
         in effect a Project Purchase Agreement, if by making such Project Loan,
         the aggregate amount of Project Loans (including the Project Loan at
         issue) in respect of Projects for which there are not then in effect
         Project Purchase Agreements would be greater than Fifteen Million
         Dollars ($15,000,000). For purposes of calculating the aggregate amount
         of Project Loans in the preceding sentence, the maximum principal
         amounts available thereunder shall be used, and not the then
         outstanding principal balances thereof. In no event shall the Bank be
         obligated to make any Project Loan on or after the Project Loan
         Commitment Expiration Date. Notwithstanding the foregoing, subject to
         the terms and conditions hereof, the Bank shall fund after the Project
         Loan Commitment Expiration Date any Project Loan for which the Closing
         has occurred prior to the Project Loan Commitment Expiration Date.

         3. SECTION 4.01 (INITIAL PROJECT LOAN ADVANCE) OF THE LOAN AGREEMENT.
The following paragraphs of Section 4.01 of the Loan Agreement are hereby
modified in their entirety to read as follows:

                  k. COST BREAKDOWN. Such Borrower shall have furnished to the
         Bank for its review and approval a Cost Breakdown reflecting all
         Project Costs for the Project in respect of which such Project Loan is
         being made. Such Cost Breakdown shall (i) include a contingency for
         Direct Costs in an amount of not less than three percent (3%) of the
         total Direct Costs for such Project, (ii) include a contingency for
         Indirect Costs in an amount of not less than three percent (3%) of the
         total Indirect Costs for such Project, and (iii) have an interest carry
         of not less than five (5) months of interest on the Project Loan,
         assuming an interest rate of eight percent (8%).

                  aa. DEBT SERVICE  COVERAGE.  The Debt  Service  Coverage
         for the Project in respect of which such Project Loan is being made is
         no less than 1.10 to 1.0.

         4. EXPENSES. Borrower shall pay all costs incidental to this
Modification, including but not limited to title insurance, survey charges,
reasonable attorneys' fees, appraisals, insurance, inspecting engineers'
and/or architect's fees, environmental fees, and all other incidental
expenses of Bank.

         5. REPRESENTATIONS AND WARRANTIES. Developer hereby represents and
warrants to Bank that there does not presently exist any default under the
Loan Agreement or any event which with the notice or lapse of time or both
would constitute a default under the Loan Agreement and that each of the
representations and warranties set forth in the Loan Agreement remain true
and correct as of the date hereof, except to the extent said representations
and warranties specifically apply to those items explicitly modified by or
otherwise disclosed in this Modification, and each of said representations
and warranties is hereby incorporated herein by reference and modified as
necessary to apply to and cover the undertakings of Developer evidenced by
this Modification.

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         6. CONTINUING EFFECT. All other terms, conditions, provisions,
representations and warranties set forth in the Loan Agreement not
specifically relating to those items explicitly modified by or otherwise
disclosed in this Modification shall remain unchanged and shall continue in
full force and effect. This Modification shall, wherever possible, be
construed in a manner consistent with the Loan Agreement; provided, however,
in the event of any irreconcilable inconsistency between the terms of this
Modification and the terms of the Loan Agreement, the terms of this
Modification shall control.

         7. WAIVER. No provision hereof shall constitute a waiver of any of
the terms or conditions of the Loan Agreement, other than those terms or
conditions explicitly modified or otherwise affected hereby.

         IN WITNESS WHEREOF, Developer and Bank have caused this Seventh
Modification of Master Construction Loan Agreement to be duly executed as of
the date and year first above written.

                                      "DEVELOPER"

                                  TRAMMELL CROW BTS, INC.,
                                  a Delaware corporation

                                  By: /s/ WILLIAM E. RYAN
                                      ------------------------------------------

                                  Printed: WILLIAM E. RYAN
                                           -------------------------------------

                                  Title: VICE PRESIDENT
                                         ---------------------------------------

                                      "BANK"

                                  KEYBANK NATIONAL ASSOCIATION, a national
                                  banking association

                                  By: /s/ THEODORE J. LEWIS
                                      ------------------------------------------

                                  Printed: THEODORE J. LEWIS
                                           -------------------------------------

                                  Title: VICE PRESIDENT
                                         ---------------------------------------


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STATE OF COLORADO )
                  ) SS:
COUNTY OF DENVER  )

         Before me, a Notary Public in and for said County and State,
personally appeared William E. Ryan, known to me to be the Vice President of
TRAMMELL CROW BTS, INC., a Delaware corporation, and acknowledged the
execution of the foregoing for and on behalf of said corporation.

         Witness my hand and Notarial Seal, this 11th day of November, 1999.

                                      /s/ SARA GIACALONE
                                      ------------------------------------------
                                      Notary Public - Signature

                                      SARA GIACALONE
                                      ------------------------------------------

                                      Notary Public - Printed

My Commission Expires:                My County of Residence:
06/30/01                              DENVER
-----------------------------         ------------------------------------------

STATE OF INDIANA  )
                  ) SS:
COUNTY OF MARION  )

         Before me, a Notary Public in and for said County and State,
personally appeared Theodore J. Lewis, known to me to be a Vice President of
KEYBANK NATIONAL ASSOCIATION, a national banking association, and
acknowledged the execution of the foregoing for and on behalf of said
association.

         Witness my hand and Notarial Seal, this 15th day of November, 1999.

                                      /s/ JANE E. BUTLER
                                      ------------------------------------------

                                      Notary Public - Signature
                                      JANE E. BUTLER
                                      ------------------------------------------

                                      ------------------------------------------
                                      Notary Public - Printed

My Commission Expires:                My County of Residence:
03/04/01                              HAMILTON
-----------------------------         ------------------------------------------

This instrument was prepared by Dennis A. Johnson, Attorney at Law, JOHNSON,
SMITH, PENCE, & HEATH, LLP, One Indiana Square, Suite 1800, Indianapolis,
Indiana 46204.

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