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                                                                   EXHIBIT 10.13

                  FIRST AMENDMENT TO PURCHASE AND SALE CONTRACT

        THIS FIRST AMENDMENT TO PURCHASE AND SALE CONTRACT (this "AMENDMENT") is
made and entered into as of May 3, 2004 by and between CRESCENT REAL ESTATE
FUNDING VIII, L.P., a Delaware limited partnership (hereinafter referred to as
"SELLER"), and HARVARD PROPERTY TRUST, LLC, a Delaware limited liability
company, dba Behringer Harvard Funds (hereinafter referred to as "PURCHASER").

                                    RECITALS:

        A.      Seller and Purchaser have entered into that certain Purchase and
Sale Contract with an Effective Date of April 2, 2004, relating to certain real
property located at 5050 Quorum Drive, Addison, Texas more particularly
described therein (the "CONTRACT").

        B.      Seller and Purchaser desire to amend the Contract as set forth
herein.

        NOW, THEREFORE, in consideration of the recitals and the mutual
covenants and agreements of the parties as herein set forth, and for other good
and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, Purchaser and Seller hereby agree as follows:

        1.      DEFINED TERMS. Capitalized terms not defined herein shall have
the same meaning ascribed to them in the Contract.

        2.      TITLE REVIEW. Section 5.4.1 of the Contract is deleted in its
entirety and replaced with the following language:

                5.4.1   TITLE REVIEW. On April 30, 2004, Seller received in
        writing Purchaser's Title Objections. By 5:00 p.m. May 4, 2004, Seller
        will notify Purchaser in writing that Seller will either satisfy the
        Title Objections at Seller's sole cost and expense, or that Seller
        cannot or will not satisfy certain Title Objections at Seller's expense.
        Failure by Seller to timely respond shall be deemed Seller's decision
        not to cure any Title Objections. If Seller elects not to satisfy any of
        the Title Objections, Purchaser has the option (as its sole remedy),
        exercisable at any time prior to 5:00 p.m., Dallas, Texas time on
        Friday, May 7, 2004 ("TITLE REVIEW TERMINATION DATE"), of either (i)
        waiving the unsatisfied Title Objections, in which event the unsatisfied
        Title Objections will become Permitted Exceptions, or (ii) terminating
        this Contract and receiving back the Earnest Money (less the Independent
        Contract Consideration), in which latter event Seller and Purchaser will
        have no further obligations, one to the other, with respect to the
        subject matter of this Contract, except for return of the Earnest Money
        (less the Independent Contract Consideration) and other provisions that
        survive termination of this Contract by their terms. In order to
        terminate this Contract pursuant to the preceding sentence, Purchaser
        shall deliver to Seller written notice ("TITLE TERMINATION NOTICE") of
        the specific Title Objection(s) pursuant to which Purchaser is
        terminating the Contract and the reason Purchaser deems such matter(s)
        to be objectionable. Purchaser's failure to deliver a Title

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        Termination Notice prior to the Title Review Termination Date shall
        constitute Purchaser's waiver of any Title Objection that Seller has
        elected not to satisfy.

        3.      CLOSING DATE. Section 9.1 of the Contract is deleted in its
entirety and replaced with the following language:

        9.1     CLOSING DATE. The consummation of this transaction (the
        "CLOSING") will take place at the offices of the Title Company, or at
        such other location upon which Seller and Purchaser mutually agree,
        before 1:00 p.m. on June 2, 2004 (the "CLOSING DATE"), unless (i) Seller
        and Purchaser mutually agree to an earlier date, or (ii) Purchaser
        extends the Closing Date to July 2, 2004 pursuant to SECTION 4.1.3.

        4.      EXTENSION EARNEST MONEY. The first sentence of Section 4.1.3 of
        the Contract is deleted in its entirety and replaced with the following
        language:

        4.1.3   EXTENSION EARNEST MONEY. At any time after Purchaser deposits
        the Additional Earnest Money but before June 2, 2004, Purchaser shall
        have the option to extend such Closing Date to occur before 1:00 p.m. on
        July 2, 2004 (the "EXTENSION OPTION").

        5.      OPTION TO TERMINATE. Seller and Purchaser acknowledge and agree
that Purchaser's option to terminate the Contract pursuant to Section 6.6 of the
Contract has expired.

        6.      RATIFICATION. The terms of the Contract, as heretofore amended,
are hereby ratified and confirmed by Purchaser and Seller.

        7.      EXECUTION. This Amendment may be executed in any number of
counterparts, each of which shall be deemed an original, and all of which shall
constitute one and the same Amendment. The delivery of counterpart signatures by
facsimile transmission shall have the same force and effect as the delivery of a
signed original hard copy.

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        IN WITNESS WHEREOF, the parties hereto have executed this Amendment
effective as of the date first written above.

                                      SELLER:

                                      CRESCENT REAL ESTATE FUNDING VIII, L.P.,
                                      a Delaware limited partnership

                                      By:  CRE Management VIII, LLC, a Delaware
                                           limited liability company, Its
                                           General Partner

                                           By:  CRESCENT REAL ESTATE
                                                EQUITIES, LTD., a Delaware
                                                corporation, Its Manager

                                                By:____________________________
                                                   Clifford M. Rudolph
                                                   Vice President, Investments


                                      PURCHASER:

                                      HARVARD PROPERTY TRUST, LLC,
                                      a Delaware limited liability company


                                      By:_______________________________________
                                      Name:_____________________________________
                                      Title:____________________________________