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                                                                    EXHIBIT 10.7

                 FIRST AMENDMENT TO PURCHASE AND SALE AGREEMENT


        THIS FIRST AMENDMENT TO PURCHASE AND SALE AGREEMENT ("AMENDMENT") is
entered into to be effective as of the 20 day of January, 2004, by and between
OLY UPTOWN GENERAL PARTNERSHIP, a Texas general partnership ("SELLER"), and PRG
REALTY PARTNERS, LTD., a Texas limited partnership ("PURCHASER"). All
capitalized terms used herein and not otherwise defined herein shall have the
meanings ascribed to them in the Purchase Agreement (defined below).

                              W I T N E S S E T H:

        WHEREAS, Seller and Purchaser previously entered into that certain
Purchase and Sale Agreement (1909 Woodall Rodgers Freeway) dated as of December
22, 2003 (the "PURCHASE AGREEMENT"), pursuant to which Seller agreed to sell to
Purchaser and Purchaser agreed to purchase the Property described therein.

        WHEREAS, Seller and Purchaser now desire to amend the Purchase Agreement
in certain respects, as hereinafter set forth.

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

        1.      COOPERATION WITH AUDIT. Purchaser has advised Seller that
Purchaser must cause to be prepared up to three (3) years of audited financial
statements in respect of the Property. Seller agrees to use commercially
reasonable efforts to cooperate with Purchaser's auditors in the preparation of
such audited financial statements, provided, however, the foregoing shall not be
construed to obligate Seller to increase or expand its duties and obligations
hereunder nor shall Seller be required to incur any expense in connection
therewith. Without limiting the generality of the preceding sentence (a) Seller
shall, during normal business hours, allow Purchaser's auditors reasonable
access to the books and records maintained by Seller in respect of the Property;
and (b) Seller shall use commercially reasonable efforts to provide to Purchaser
such financial information and supporting documentation relating to the Property
as are necessary for Purchaser's auditors to prepare audited financial
statements; and (c) if Seller has audited financial statements with respect to
the Property, Seller shall promptly provide Purchaser's auditors with a copy of
such audited financial statements. If after Closing Seller obtains an audited
financial statement in respect of the Property for a fiscal period in 2003 or
2004 that was not completed at the time of Closing, then Seller shall promptly
provide Purchaser with a copy of such audited financial statement, and the
foregoing covenant shall survive Closing. In no event shall the foregoing
require Seller to provide Purchaser access to books and records (i) subject to
attorney-client and/or work product privilege, (ii) subject to confidentiality
policies or provisions, or (iii) subject to Seller's internal financial
analysis, nor shall it require Seller to obtain or otherwise create audited
financial statements.

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        2.      RIGHT TO MAKE DISCLOSURE. Notwithstanding anything contained in
the Agreement to the contrary, Purchaser shall be permitted (a) to make such
disclosures to potential investors in the Property as may be recommended by
Purchaser's legal counsel; and (b) to make such other disclosures as may be
recommended by Purchaser's legal counsel in order to comply with all financial
reporting, securities laws and other laws applicable to Purchaser.

        3.      DELETION OF REPRESENTATION. Purchaser has advised Seller that
the Source may include assets of an "employee benefit plan" as defined in
Section 3(3) of ERISA or a "plan" as defined in Section 4975(a) of the Internal
Revenue Code of 1986, as amended. Accordingly, the representation made by
Purchaser in clause (d) of Section 4.3 of the Purchase Agreement is hereby
deleted in its entirety.

        4.      MODIFICATION OF DATE REFERENCE. The references to "January 10,
2004" that appear in clauses (i) and (ii) of Section 6.1 of the Purchase
Agreement are hereby deleted and references to "January 19, 2004" are hereby
inserted in lieu thereof.

        5.      ESTOPPEL AND SNDA. The form of Estoppel attached hereto and
labeled EXHIBIT D-1 shall be substituted for EXHIBIT D-1 attached to the
Purchase Agreement; provided, however, that the Estoppel to be executed by Bank
One Texas, N.A. shall be in the form of the estoppel attached hereto and labeled
EXHIBIT D-1A. The form of SNDA attached hereto and labeled EXHIBIT D-2 shall be
substituted for EXHIBIT D-2 attached to the Purchase Agreement.

        5.      CONSENT TO ASSIGNMENT. Purchaser has advised Seller that
Purchaser intends to assign its rights and obligations under the Purchase
Agreement to a limited partnership (the "PERMITTED ASSIGNEE") in which only
Purchaser and Behringer Harvard Short-Term Opportunity Fund I LP, a Texas
limited partnership (or affiliates of such parties) will be partners. Seller
hereby consents to such assignment, subject to execution by the Permitted
Assignee of the Assignment of Purchase and Sale Agreement attached to the
Purchase Agreement as EXHIBIT D (with such modifications thereto as may be
necessary to make same consistent with the provisions of this Amendment).

        6.      EFFECT OF AMENDMENT. This Amendment modifies and amends the
Purchase Agreement and the terms and provisions hereof shall supersede and
control over any contrary or conflicting terms and provisions set forth in the
Purchase Agreement. The Purchase Agreement, as amended by this Amendment,
remains in full force and effect.

        7.      COUNTERPARTS. To facilitate execution of this Amendment, this
Amendment may be executed in multiple counterparts, each of which, when
assembled to include an original signature for each party contemplated to sign
this Amendment, will constitute a complete and fully executed original. All such
fully executed original counterparts will collectively constitute a single
agreement.

        8.      FACSIMILE SIGNATURES. In order to expedite the transaction
contemplated herein, telecopied or facsimile signatures may be used in place of
original signatures on this Amendment. Seller and Purchaser intend to be bound
by the signatures on the telecopied document, are aware that the other party
will rely on the telecopied signatures, and hereby waive any defenses to the
enforcement of the terms of this Amendment based on the form of signature.


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        IN WITNESS WHEREOF, the parties hereto have executed this Amendment to
be effective the date and year first above written.


                           SELLER:

                           OLY UPTOWN GENERAL PARTNERSHIP, a Texas general
                           partnership

                           By: Oly Uptown GP, L.P.
                               Its Managing General Partner

                               By: Oly Texas GP II, LLC
                                   Its General Partner

                                   By: /s/ Ron J. Hoyl
                                      ---------------------------------
                                   Name:   Ron J. Hoyl
                                        -------------------------------
                                   Title:  Vice President
                                         ------------------------------




                           PURCHASER:

                           PRG REALTY PARTNERS, LTD, a Texas limited partnership

                           By: PRG Realty, Inc., its General Partner

                               By: /s/ Jon Mark Robertson
                                  -------------------------------------
                               Name:   Jon Mark Robertson
                                    -----------------------------------
                               Title:  President
                                     ----------------------------------



                               By: /s/ William Andrew Peterson, Jr.
                                  -------------------------------------
                               Name:   William Andrew Peterson, Jr.
                                    -----------------------------------
                               Title:  CEO
                                     ----------------------------------


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