Document:

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                                                                   EXHIBIT 10.31

                      FOURTH AMENDMENT TO CONTRACT OF SALE

        This FOURTH AMENDMENT TO CONTRACT OF SALE (this "Amendment") is made and
entered into effective as of the ____ day of ____________, 2004 (the "Effective
Date"), by and among VORTISCH HOLDINGS, L.P., a Texas limited partnership
("Seller"), CANTEX REALTIES, INC., a Texas corporation ("Cantex"), and REALTY
AMERICA GROUP I, LP, a Texas limited partnership ("Original Purchaser"), and
REALTY AMERICA GROUP (4245 CENTRAL), LP, a Texas limited partnership
("Purchaser").

        WHEREAS, Seller, Cantex and Purchaser have entered into that certain
Contract of Sale (the "Contract") dated effective April 19, 2004 concerning
property commonly known as 4245 N. Central Expressway, located in Dallas, Dallas
County, Texas (the "Property"); and

        WHEREAS, Purchaser, Cantex and Seller desire to extend the expiration
date of the Inspection Period to June 25, 2004; and

        WHEREAS, the parties agree to extend the expiration date of the
Inspection Period to June 25, 2004.

        NOW, THEREFORE, for and in consideration of Ten Dollars ($10.00) and
other good and valuable consideration, the receipt and sufficiency of which is
hereby acknowledged, the parties hereto agree to amend the Contract as follows:

        Pursuant to the terms of the Contract and the Third Amendment, the
Inspection Period is hereby extended to Friday, June 25, 2004.

        Except as specifically modified by this Amendment, all of the other
terms and provisions of the Contract shall remain in full force and effect, and
are hereby ratified and confirmed by Seller, Cantex and Purchaser.
Notwithstanding the foregoing, in the event there is any conflict between the
terms and provisions of the Contract and this Amendment, the terms and
provisions of this Amendment shall control.

        This Amendment may be executed in any number of counterparts, each of
which shall be deemed an original. Facsimile copies of the signature pages to
this Amendment shall be deemed to be originals for all purposes of this
Amendment.

        IN WITNESS WHEREOF, Seller, Cantex, Original Purchaser, and Purchaser
have caused this Amendment to be duly executed as of the Effective Date.

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                                SELLER:

                                VORTISCH HOLDINGS, L.P.,
                                a Texas limited partnership

                                By: VORTISCH INVESTMENTS, INC.,
                                    a Delaware corporation
                                    its general partner

                                    By:
                                             -----------------------------------
                                             Hermann Vortisch
                                             President

                                    Date of signature ___________________, 2004

                                ORIGINAL PURCHASER:

                                REALTY AMERICA GROUP I, LP,
                                a Texas limited partnership

                                By: REALTY AMERICA GROUP, LLC,
                                    a Texas limited liability company
                                    its general partner

                                    By:
                                             -----------------------------------
                                             Webb M. Sowden, III
                                             Member

                                    Date of Signature: _______________, 2004

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                                PURCHASER:

                                REALTY AMERICA GROUP (4245 CENTRAL), LP,
                                a Texas limited partnership

                                By: REALTY AMERICA GROUP INVESTMENTS, LLC,
                                    a Texas limited liability company
                                    its general partner

                                    By:
                                             -----------------------------------
                                             Webb M. Sowden, III
                                             Member

                                    Date of Signature: ___________________, 2004

                                CANTEX:

                                CANTEX REALTIES, INC.,
                                a Texas corporation

                                By:
                                      ------------------------------------------
                                Name:
                                      ------------------------------------------
                                Its:
                                      ------------------------------------------

                                Date of Signature: _______________________, 2004<PAGE>

                                                                   EXHIBIT 10.32

                       FIFTH AMENDMENT TO CONTRACT OF SALE

        This FIFTH AMENDMENT TO CONTRACT OF SALE (this "Amendment") is made and
entered into effective as of the ____ day of June, 2004 (the "Effective Date"),
by and among VORTISCH HOLDINGS, L.P., a Texas limited partnership ("Seller"),
CANTEX REALTIES, INC., a Texas corporation ("Cantex"), and REALTY AMERICA GROUP
(4245 CENTRAL), LP, a Texas limited partnership ("Purchaser").

                             PRELIMINARY STATEMENTS:

        The following preliminary statements are a material part of this
Amendment:

        A.      Seller, Cantex and Realty America Group I, LP, as predecessor in
interest to Purchaser made and entered into that certain Contract of Sale, dated
effective April 16, 2004 (the "Original Contract"), with respect to certain real
property located on that certain tract or parcel of land situated in the City of
Dallas, Dallas County, Texas, which is more particularly described in the
Contract (the "Property"); as amended by that certain First Amendment to
Contract of Sale (the "First Amendment"); as amended by that certain Second
Amendment to Contract of Sale (the "Second Amendment"); as amended by that
certain Third Amendment to Contract of Sale (the "Third Amendment"); as further
amended by that certain Fourth Amendment to Contract of Sale (the "Fourth
Amendment")(the Contract, the First Amendment, the Second Amendment, the Third
Amendment, and the Fourth Amendment are hereinafter collectively referred to as
the "Contract").

        B.      Cantex is only a party to this Amendment and the Contract as is
necessary for Purchaser to enforce certain representations and warranties
provided by Cantex to Purchaser under the Contract.

        C.      Seller, Cantex, and Purchaser desire to amend the Contract as
set forth below.

                                   AGREEMENTS:

        NOW THEREFORE, in consideration of the agreements to sell and purchase
the Property and the mutual covenants and agreements contained in this Amendment
and in the Contract, and other good and valuable consideration, the receipt and
adequacy of which are hereby acknowledged, Seller, and Purchaser hereby agree as
follows:

1.      PURCHASE PRICE. Pursuant to the terms of the Contract, the Purchase
        Price for the Property is Eight Million Two Hundred Thousand and No/100s
        Dollars ($8,200,000.00). Seller and Purchaser hereby agree that the
        Purchase Price shall be amended to reflect a Purchase Price under the
        Contract of Seven Million Seven Hundred Seventy Five Thousand and
        No/100s Dollars ($7,775,000.00). Any reference in the Contract to the
        Purchase Price shall mean $7,775,000.00.

2.      INSPECTION PERIOD. Upon the full execution of this Amendment by
        Purchaser, Seller and Cantex, the Inspection Period shall be deemed to
        have expired.

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3.      EARNEST MONEY. The Earnest Money and Extension Deposit deposited by
        Purchaser under the Contract shall be nonrefundable following the
        execution of this Amendment by Purchaser, Seller and Cantex.

4.      CLOSING DATE. Purchaser and Seller hereby agree that, notwithstanding
        anything in the Contract to the contrary, the Closing Date under the
        Contract shall be Friday, July 30, 2004.

5.      TERMINATION OF CONTRACT. In the event Seller, Cantex and Purchaser have
        not executed, and delivered to the other parties, this Amendment prior
        to the expiration of the Inspection Period set forth in the Contract,
        the Contract shall terminate, and be of no further force or effect, and
        the Earnest Money and Extension Deposit heretofore deposited by
        Purchaser shall be immediately returned to Purchaser. Such termination
        shall take effect without any further documentation on the part of
        Seller, Cantex or Purchaser.

6.      CAPITALIZED TERMS. Capitalized terms used but not defined in this
        Amendment shall have the same meaning as those in the Contract, unless
        otherwise noted herein.

7.      RATIFICATION OF CONTRACT. Except as specifically modified by this
        Amendment, all of the other terms and provisions of the Contract shall
        remain in full force and effect, and are hereby ratified and confirmed
        by Seller, Cantex and Purchaser. Notwithstanding the foregoing, in the
        event there is any conflict between the terms and provisions of the
        Contract and this Amendment, the terms and provisions of this Amendment
        shall control.

8.      REPRESENTATIONS AND WARRANTIES. Seller, Cantex, and Purchaser represent
        and warrant to each other respectively that they have the requisite
        power and authority to enter into this Amendment; that all necessary and
        appropriate approvals, authorizations and other steps have been taken to
        effect the legality of this Amendment; that the signatories executing
        this Amendment are authorized to do so on behalf of Seller, Original
        Purchaser and Purchaser; and that this Amendment is valid and binding
        upon and enforceable against Seller, Cantex, and Purchaser.

9.      COUNTERPARTS. This Amendment may be executed in any number of
        counterparts, each of which shall be deemed an original. Facsimile
        copies of the signature pages to this Amendment shall be deemed to be
        originals for all purposes of this Amendment.

10.     FINAL AGREEMENT. This Amendment and the Contract cover in full, each and
        every final agreement of every kind or nature whatsoever between Seller,
        Cantex, and Purchaser concerning the Property, and all preliminary
        negotiations and agreements whatsoever of every kind or nature are
        merged into this Amendment and the Contract. This Amendment and the
        Contract cannot be changed or modified in any manner other than by
        written amendment or modification executed by Seller, Cantex and
        Purchaser.

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11.     SUCCESSORS AND ASSIGNS. This Amendment is binding upon and inures to the
        benefit of Seller, Cantex and Purchaser and their respective successors
        and assigns.

        IN WITNESS WHEREOF, Seller, Cantex, and Purchaser have caused this
Amendment to be duly executed as of the Effective Date.

                                SELLER:

                                VORTISCH HOLDINGS, L.P.,
                                a Texas limited partnership

                                By: VORTISCH INVESTMENTS, INC.,
                                    a Delaware corporation
                                    its general partner

                                    By:
                                             -----------------------------------
                                             Hermann Vortisch
                                             President

                                    Date of Signature: June ____, 2004

                                PURCHASER:

                                REALTY AMERICA GROUP (4245 CENTRAL), LP,
                                a Texas limited partnership

                                By: REALTY AMERICA GROUP INVESTMENTS, LLC,
                                    a Texas limited liability company
                                    its general partner

                                    By:
                                             -----------------------------------
                                             Webb M. Sowden, III
                                             Member

                                    Date of Signature: June  ____, 2004

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                                CANTEX:

                                CANTEX REALTIES, INC.,
                                a Texas corporation

                                By:
                                      ------------------------------------------
                                Name:
                                      ------------------------------------------
                                Its:
                                      ------------------------------------------

                                Date of Signature: June  ____, 2004

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