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                                                                   EXHIBIT 10.04

                    FIRST AMENDMENT TO AGREEMENT OF PURCHASE

         THIS FIRST AMENDMENT TO AGREEMENT OF PURCHASE (this "Amendment") is
entered into effective as of the 19th day of February, 2004 by and between 2350
NORTH BELT, L.P., a Georgia limited partnership (hereinafter "Seller"), and
TRIPLE NET PROPERTIES, LLC, a Virginia limited liability company (hereinafter
"Purchaser").

                                   WITNESSETH:

         WHEREAS, Seller and Purchaser entered into that certain Agreement of
Purchase, dated as of January 21, 2004 (the "Agreement"), in which Seller agreed
to sell to Purchaser, and Purchaser agreed to purchase from Seller, certain real
property located in Houston, Harris County, Texas, together with all
improvements located hereon, and being more fully identified in the Agreement
(hereinafter the "Property"). Any terms that are capitalized in this Amendment
and not otherwise defined herein shall have the meanings ascribed to them in the
Agreement; and

         WHEREAS, Seller has agreed to give Purchaser a credit at Closing; and

         WHEREAS, Purchaser has performed all of its diligence and determined
that it is willing to proceed with the Agreement; and

         WHEREAS, Purchaser has agreed that its right to terminate the Agreement
pursuant to Section 6.1 of the Agreement expires of even date herewith;

         NOW, THEREFORE, in consideration of the premises, the mutual covenants
and agreements of the parties hereto, and other good and valuable consideration,
the receipt and sufficiency of which are hereby acknowledged, Seller and
Purchaser do hereby agree as follows:

1.       Earnest Money. Notwithstanding anything to the contrary in the
         Agreement, the additional earnest money deposit in the sum of One
         Hundred Fifty Hundred Thousand and No/100 Dollars ($ 150,000.00) shall
         be deposited with Escrowee on or before February 23, 2004, by 5:00
         P.M., Pacific time.

2.       Diligence and Termination Rights. Purchaser hereby acknowledges that it
         has conducted all diligence, performed all tests and made all other
         inquiries it deems necessary or appropriate in connection with its
         acquisition of the Property including, but not limited to, matters of
         title and survey, and Purchaser agrees that its right to terminate the
         Agreement pursuant to Section 6.1 of the Agreement has expired as of
         the date of this Amendment. Seller and Purchaser further agree that,
         except for the deed of trust shown as Item 5 on Schedule C to that
         certain Commonwealth Land Title Insurance Company Commitment G. F. No.
         0484008 in favor of Triple Net Properties. LLC having an

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         effective date of January 13, 2004 at 7:59 A.M. (the "Commitment"),
         which is the only Mandatory Cure Items at this time, all title matters
         disclosed on the Commitment and Purchaser's survey prepared by Sandoval
         Engineers & Surveyors. Inc., dated February 19, 2002, last revised
         January 30, 2004, are Permitted Exceptions and there are no Seller Cure
         Items at this time.

3.       Purchase Price Adjustment. Seller and Purchaser hereby acknowledge and
         agree that Section 2 of the Agreement is hereby modified to provide
         that the Purchase Price shall be reduced to Twelve Million Six Hundred
         Seventy Five Thousand and No/100 Dollars ($12,675,000). Seller shall
         not owe any commission to the Purchaser's Broker and Section 22.2 of
         the Agreement shall be modified to delete the reference to the
         Purchaser's Broker and its commission.

4.       Credit for Free Rent. Seller and Purchaser agree that Seller shall give
         Purchaser a credit at Closing in the amount of any free rent which will
         not have been fully utilized prior to Closing, including without
         limitation, any free rent under the terms of the Shawcor Lease.

5.       Estoppel and SNDA Forms. The SNDAs to be delivered by Seller pursuant
         to Section 11.8 of the Agreement shall be on the form attached hereto
         as Exhibit A, and the estoppels to be delivered by Seller pursuant to
         Sections 11.8 and 12.2 of the Agreement shall be on the form attached
         hereto as Exhibit B.

6.       REA Estoppel. It shall be an additional condition precedent to
         Purchaser's obligation to consummate the acquisition of the Property
         that prior to Closing, Seller must deliver an estoppel from the party
         or parties entitled to enforce the Reciprocal Easement Agreement dated
         December 8, 1992, as described in instrument filed under Harris County
         Clerk's No. H261377, in favor of Purchaser and Purchaser's lender,
         which certifies that that there are no current violations of any
         restrictions which the Association is entitled to enforce, no monetary
         amounts are due which have not yet been paid.

7.       Closing Date. Purchaser and Seller hereby acknowledge and agree that
         the Closing Date shall occur on or before 2:00 P.M., local Texas time,
         on April 1, 2003.

8.       Rent Guaranty Escrow.

         a.       At Closing. Escrowee shall create an escrow to hold funds to
                  be used as a rent guaranty (the "Rent Guaranty Escrow"), and
                  shall withhold from Seller's proceeds at Closing the total
                  sum of Two Hundred Sixty Thousand Four Hundred Thirty Six and
                  50/100 Dollars ($260,436.50) and shall transfer such funds
                  into the Rent Guaranty Escrow, to be distributed as provided
                  herein, The Rent Guaranty Escrow is intended to guaranty
                  twelve months of rent payment for the entire leasable area of
                  the 6th Floor of the Building (15,595 square feet) (the
                  "Guarantied Premises") at an annual rental rate of $16.70 per
                  square foot (the "Agreed Rental Rate") and for a term of
                  twelve (12) months commencing on the Closing Date.

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         b.       All amounts in the Rent Guaranty Escrow shall be placed in an
                  interest bearing account with a national banking association.
                  All interest accrued on amounts in the Rent Guaranty Escrow
                  shall inure to the benefit of Seller.

         c.       Purchaser agrees that, except for the Pending GSA Lease
                  described below, Purchaser shall be responsible for any
                  leasing costs attributable to the Guarantied Premises which
                  arise after Closing.

         d.       Funds shall be disbursed from the Rent Guaranty Escrow as
                  provided for in this subparagraph, At Closing, for all
                  portions of the Guarantied Premises for which rent has not
                  been collected for the month in which Closing occurs, Escrowee
                  shall immediately disburse to Purchaser from the Rent Guaranty
                  Escrow an amount equal to the rent attributable to such
                  portions of the Guarantied Premises which would have been
                  prorated to the Purchaser if rent for the month in which
                  Closing occurs for such portions of the Guarantied Premises
                  had been paid on time in the amount of the Agreed Rental Rate.
                  On the fifth business day of each calendar month commencing
                  the month after Closing, Escrowee shall disburse Twenty One
                  Thousand Seven Hundred Three and 4/100ths Dollars ($21,703.04)
                  (a "Monthly Disbursement") from the Rent Guarantee Escrow, as
                  follows: (A) to Seller an amount equal to the rent actually
                  received by Purchaser by the third business day of the month
                  from tenants for the Guarantied Premises during the previous
                  calendar month (whether such rent is attributable to the
                  current month or any month previous to the disbursement but
                  after Closing); and (B) to the Purchaser, the balance of the
                  Monthly Disbursement. In the event that, under the terms of
                  clause (A) in the preceding sentence, the Seller is entitled
                  to receive more than a particular Monthly Disbursement, the
                  Escrowee shall withhold from the subsequent Monthly
                  Disbursement the amount necessary to pay seller the amount to
                  which seller is entitled, For purposes of determining what
                  rent has been received by the Purchaser by the third business
                  day of a particular month, the Escrowee may rely on a written
                  representation by the Purchaser, unless the Seller provides
                  evidence of payment reasonably satisfactory to the Escrowee.
                  On the one year anniversary of Closing, the balance of the
                  Rent Guaranty Escrow shall be disbursed to Purchaser, and no
                  party shall have any further rights or liabilities relating to
                  the Rent Guaranty Escrow.

         e.       Purchaser acknowledges that Seller currently has an offer
                  pending with the GSA to lease approximately 8,200 square feet
                  of the Guarantied Premises, at the same terms as the existing
                  GSA lease, with a landlord TI allowance of $10,841.24 and
                  leasing commission of four percent (the "Pending GSA Lease").
                  Purchaser agrees to lease any portion of the Guarantied
                  Premises to GSA substantially on the terms described in
                  Exhibit A. Seller shall be responsible for all leasing costs
                  (including tenant improvement costs and leasing commissions)
                  payable with respect to the Pending GSA Lease. Purchaser
                  agrees to permit the GSA to terminate its existing

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                  lease of Suite 100 in the Building at no cost to GSA, upon
                  execution by GSA of the Pending GSA Lease. For purposes of
                  calculating the portion of each Monthly Disbursement to be
                  released to Seller, with respect to the Pending GSA Lease,
                  Escrowee shall release to Seller an amount which is equal to
                  the rent paid by GSA pursuant to the Pending GSA Lease, less
                  the rent which would have been paid by the GSA under its
                  existing lease of Suite 100.

         f.       Seller and Purchaser both shall use diligent efforts to lease
                  all portions of the Master Lease Premises during the term of
                  the Master Lease; provided, however that any lease of such
                  space must be acceptable to Purchaser in its commercially
                  reasonable discretion.

         g.       Notwithstanding any provision to the contrary in the Agreement
                  or this Amendment, in no event shall either party have the
                  right to offset from the Rent Guaranty Escrow any claims
                  arising out of the Agreement.

         h.       The fees charged by the Escrowee for handling the Rent
                  Guaranty Escrow shall be shared equally between the Seller and
                  Purchaser and shall be paid at Closing.

9.       Ratification. Except as expressly set forth in this Amendment, the
         Agreement remains unmodified and unchanged as reinstated hereby and
         Seller and Purchaser hereby ratify and affirm the Agreement as hereby
         amended and reinstated.

10.      Counterparts. This Amendment may be executed in multiple counterparts,
         each of which shall be deemed an original and all of which shall
         constitute one agreement and the signatures of any party to any
         counterpart shall be deemed to be a signature to, and may be appended
         to, any other counterpart. This Amendment may be delivered by
         facsimile, and such facsimile counterparts shall be valid and binding
         on the parties with the same effect as if original signatures had been
         exchanged

                     [SIGNATURES COMMENCE ON FOLLOWING PAGE]

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         IN WITNESS WHEREOF, Seller and Purchaser have executed this First
Amendment as of the effective date first set forth above.

SELLER:                               2350 NORTH BELT, L.P.,
                                      a Georgia limited partnership

                                      By:     GIG-2350 North Belt, L.P., a
                                              Georgia Limited partnership, its
                                              general partner

Date:                                         BY: /s/ Robert C. Goddard
     -------------------------                    ------------------------------
                                                  Name: Robert C. Goddard, III
                                                  Its: General Partner

PURCHASER:                            TRIPLE NET PROPERTIES, LLC, a
                                      Virginia limited liability company

Date: 2-20-04                         By: /s/  Tony Thompson
                                          --------------------------------------
                                          Name: Tony Thompson
                                          Its: President

CONSENTED AND AGREED TO BY PURCHASER'S BROKER:

                                      TRIPLE NET PROPERTIES REALTY, INC.
                                      a California corporation

                                      BY: /s/  Tony Thompson
                                          --------------------------------------
                                      Name: Tony Thompson
                                      Its: President

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