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               SIXTH MODIFICATION OF MASTER CONSTRUCTION LOAN AGREEMENT


     THIS SIXTH MODIFICATION, dated and effective as of May 31, 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,  and as
modified by that certain Fifth Modification of Master Construction Loan
Agreement between Developer and Bank, dated April 23, 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 terms:

          "Approved Tenant" shall mean OfficeMax, Inc. and any other tenant
     approved by Bank in its sole discretion.

          "Debt Service Coverage Ratio" shall mean the ratio of (i) projected
     total annual income to be received under the Lease for an applicable
     Project, defined as base rent, common area maintenance payments,
     insurance and real estate tax reimbursements and miscellaneous sources,
     less projected total annual expenses for such Project, defined as an
     annual management fee in an amount equal to Three Percent (3%) of the
     projected total annual income of such Project, an annual charge of Ten
     Cents ($.10) per square foot of such Project for a capital reserve and
     expense of common area maintenance, insurance, real estate taxes, and
     non-capitalized repairs, to (ii) the projected total annual sum of all
     interest payments and principal payments on the applicable Project Loan
     which would be due and

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     payable assuming the level amortization of such Project Loan over a
     period equal to the lesser of (a) twenty (20) years or (b) the term of
     the Lease for the Project, plus five (5) years, at a per annum interest
     rate equal to One and Three Quarters Percent (1.75%) above the most
     recent weekly average yield on United States Treasury Securities
     adjusted to a constant maturity of ten (10) years.

          "Plans and Specifications" shall mean the plans and specifications
     for the construction of the Improvements on an applicable Project Site
     prepared by the Architect therefor and approved on or prior to the date
     of the initial Advance for the applicable Project by the Borrower, the
     Bank, the Approved Tenant leasing such Project and the Contractor,
     including all working drawings and shop drawings prepared for use in
     connection therewith, as the same may be finalized, supplemented,
     modified or amended from time to time by Change Orders permitted
     hereunder.

          "Project Loan Commitment Expiration Date" shall mean September 30,
     1999.

     2.   REFERENCE TO OFFICEMAX IN THE LOAN AGREEMENT.  The reference to
"OfficeMax" is hereby deleted in the following sections contained in the Loan
Agreement:

     Section 4.01 (e)(ii)
     Section 4.01 (v)(ii)
     Section 6.05
     Section 8.01 (l)
     Number 6 of Exhibit B

     3.   SECTION 4.01 OF THE LOAN AGREEMENT.  Paragraph n. of Section 4.01
of the Loan Agreement shall be amended in its entirety to read as follows:

          n.   CONSTRUCTION CONTRACT. Such Borrower shall have furnished to
     the Bank for its review and approval a copy of the executed Construction
     Contract for the construction of the Improvements forming a part of the
     Project in respect of which such Project Loan is being made in
     accordance with the Plans and Specifications therefor for a maximum
     fixed price not exceeding an amount approved by the Bank. Such Borrower
     shall also furnish to the Bank copies of all other Major Contracts in
     respect of such Project. Such Major Contracts shall be subject to
     reasonable approval by the Bank.

          Such Construction Contract shall further provide:

                 i. A provision that with final payment such Contractor shall
          deliver to such Borrower a complete release of liens signed by such
          Contractor and all subcontractors;

                ii. A provision that no change orders involving an increase
          in costs of Fifty Thousand Dollars ($50,000) or more for a single
          change order or One Hundred  Thousand Dollars ($100,000) or more in
          the aggregate shall

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          be effective without the prior written consent of the Bank and, to
          the extent required under the Lease for such Project, the prior
          written consent of the Approved Tenant under such Lease (this
          requirement shall be satisfied if the provision is included in the
          Contractor's Letter for such Project);

               iii. A provision for not less than Ten Percent (10%) retainage
          in connection with interim payments to each subcontractor (but not
          for payments to suppliers unless Bank determines in its reasonable
          discretion that such retainage as to suppliers is appropriate)
          until the Improvements forming a part of such Project are
          substantially completed; and

               iv.  If provided for under the laws of the state in which such
          Project is located, a no-lien provision.

               4.   SECTION 7.04 OF THE LOAN AGREEMENT.  Section 7.04 of the
Loan Agreement shall be amended in its entirety to read as follows:

          7.04.     CHANGE ORDERS. Without the Bank's prior written consent,
     such Borrower will not execute, or permit the performance of work on the
     Project in respect of which such Project Loan is being made, or the
     furnishing of Materials therefor pursuant to any Change Order involving
     an increase in the Direct Costs of such Project of Fifty Thousand
     Dollars ($50,000) or more for single Change Orders or One Hundred
     Thousand Dollars ($100,000) or more in the aggregate or involving any
     fundamental change in the architectural, mechanical or structural design
     of any portion of the Improvements forming a part of such Project, or
     involving any materially adverse change in the quality of workmanship or
     Materials in such Improvements or causing any delay in completion of
     construction of such Improvements beyond the Completion Date therefor.
     Such Borrower will deliver copies of all Change Orders to the Bank
     promptly following their execution. Such Borrower will not execute or
     permit the performance of work on such Project or the furnishing of
     Materials therefor pursuant to a Change Order without the prior written
     consent of the Approved Tenant leasing such Project, if such consent is
     required under the Lease for such Project.

     5.   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.

     6.   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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     7.   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.

     8.   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 Sixth
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/ Lucy L. Dinneen
                                 ---------------------------------------------

                              Printed: Lucy L. Dinneen
                                      ----------------------------------------

                              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 Lucy L. Dinneen, 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 28th day of July, 1999.

                              /s/ Amy J. Waters
                              ------------------------------------------------
                              Notary Public - Signature

                              Amy J. Waters
                              ------------------------------------------------
                              Notary Public - Printed

My Commission Expires:        My County of Residence:

10/06/02                      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 3rd day of August, 1999.

                              /s/ Jane E. Butler
                              ------------------------------------------------
                              Notary Public - Signature

                              Jane E. Butler
                              ------------------------------------------------
                              Notary Public - Printed

My Commission Expires:        My County of Residence:

3/4/01                        Hamilton
----------------------        ------------------------------------------------

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















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