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                                                                   EXHIBIT 10.13

                                    WARRANT

         THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED
         UNDER THE SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE SOLD,
         EXCHANGED OR TRANSFERRED IN ANY MANNER IN THE ABSENCE OF SUCH
         REGISTRATION OR AN OPINION OF COUNSEL REASONABLY ACCEPTABLE TO THE
         COMPANY THAT NO SUCH REGISTRATION IS REQUIRED.


                               WARRANT CERTIFICATE

                                    IVG CORP.



No. WR-001                  Right to Purchase 50,000 Shares of Common Stock of
Date: April 30, 2001        IVG Corp. (subject to adjustment as provided herein)

         THIS CERTIFIES THAT, for value received, UNION ATLANTIC CAPITAL, L.C.
or its registered assigns, is entitled to purchase from IVG CORP., a Delaware
corporation (the "COMPANY"), at any time or from time to time during the period
specified in Paragraph 2, 50,000 fully paid and nonassessable shares of the
Company's Common Stock, par value $0.0001 per share (the "COMMON STOCK"), at an
exercise price per share equal to $1.647 (the "EXERCISE PRICE"). The term
"WARRANT SHARES," as used herein, refers to the shares of Common Stock
purchasable hereunder. The Warrant Shares and the Exercise Price are subject to
adjustment as provided in Paragraph 4.

         This Warrant is subject to the following terms, provisions, and
conditions:

         1. MANNER OF EXERCISE; ISSUANCE OF CERTIFICATES; PAYMENT FOR SHARES.
Subject to the provisions of this Warrant Certificate, this Warrant may be
exercised by the holder of this Warrant and/or any permitted transferee
specified in Paragraph 7 below (the "holder"), in whole or in part, by the
surrender of this Warrant together with a completed exercise agreement in the
form attached to this Warrant Certificate (the "EXERCISE AGREEMENT"), to the
Company during normal business hours on any business day at the Company's
principal executive offices (or such other office or agency of the Company as it
may designate by notice to the holder), and upon payment of the Exercise Price.
At the option of the holder, the Exercise Price may be paid to the Company in
cash, by certified or official bank check or by wire transfer for the account of
the Company. The Warrant Shares so purchased shall be deemed to be issued to the
holder or such holder's designee, as the record owner of such shares, as of the
close of business on the date on which this Warrant shall have been surrendered,
the completed Exercise Agreement shall have been delivered, and payment shall
have been made for such shares as set forth above. Certificates for the Warrant
Shares so purchased shall be delivered to the holder within a reasonable time
after this Warrant shall have been so exercised. The certificates so delivered
shall be in such denominations as may be requested by the holder and shall be
registered in the name of the holder or such other name as shall be designated
by such holder.

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         2. PERIOD OF EXERCISE. This Warrant may be exercised, at the option of
the holder, in whole or in part, at any time from the date of the execution of
this Warrant and (b) ending at 5:00 p.m., Eastern time, on the fourth
anniversary of the date of this Warrant (the "Exercise Period").

         3. CERTAIN AGREEMENTS OF THE COMPANY. The Company hereby covenants and
agrees as follows:

                  (a) SHARES TO BE FULLY PAID. All Warrant Shares will, upon
         issuance in accordance with the terms of this Warrant, be validly
         issued, fully paid and nonassessable and free from all taxes, liens and
         charges with respect to the issue thereof.

                  (b) RESERVATION OF SHARES. During the Exercise Period, the
         Company shall at all times have authorized, and reserved for the
         purpose of issuance upon exercise of this Warrant, a sufficient number
         of shares of Common Stock to provide for the exercise of this Warrant.

                  (c) SUCCESSORS AND ASSIGNS. This Warrant will be binding upon
         any entity succeeding to the Company by merger, consolidation or
         acquisition of all or substantially all of the Company's assets.

         4. ANTIDILUTION PROVISIONS. During the Exercise Period, the Exercise
Price and the number of Warrant Shares shall be subject to adjustment from time
to time as provided in this Paragraph 4. In the event that any adjustment of the
Exercise Price as required herein results in a fraction of a cent, such Exercise
Price shall be rounded up to the nearest cent.

                  (a) SUBDIVISION OR COMBINATION OF COMMON STOCK. During the
         Exercise Period, if the Company subdivides (by any stock split, stock
         dividend, recapitalization, reorganization, reclassification or
         otherwise) any shares of Common Stock into a greater number of shares,
         then, after the date of record for effecting such subdivision, the
         Exercise Price in effect immediately prior to such subdivision will be
         proportionately reduced. During the Exercise Period, if the Company
         combines (by reverse stock split, recapitalization, reorganization,
         reclassification or otherwise) any shares of Common Stock into a
         smaller number of shares, then, after the date of record for effecting
         such combination, the Exercise Price in effect immediately prior to
         such combination will be proportionately increased.

                  (b) ADJUSTMENT IN NUMBER OF SHARES. Upon each adjustment of
         the Exercise Price pursuant to the provisions of this Paragraph 4, the
         number of shares of Common Stock issuable upon exercise of this Warrant
         shall be adjusted by multiplying a number equal to the Exercise Price
         in effect immediately prior to such adjustment by the number of shares
         of Common Stock issuable upon exercise of this Warrant immediately
         prior to such adjustment and dividing the product so obtained by the
         adjusted Exercise Price.

                  (c) CONSOLIDATION, MERGER OR SALE. During the Exercise Period,
         in case of any consolidation of the Company with, or merger of the
         Company into any other corporation, or in case of any sale or
         conveyance of all or substantially all of the assets of the Company

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         other than in connection with a plan of complete liquidation of the
         Company, then as a condition of such consolidation, merger or sale or
         conveyance, adequate provision will be made whereby the holder of this
         Warrant will have the right to acquire and receive upon exercise of
         this Warrant in lieu of the shares of Common Stock immediately
         theretofore acquirable upon the exercise of this Warrant, such shares
         of stock, securities or assets as may be issued or payable with respect
         to or in exchange for the number of shares of Common Stock immediately
         theretofore acquirable and receivable upon exercise of this Warrant had
         such consolidation, merger or sale or conveyance taken place. In any
         such case, the Company will make appropriate provision to insure that
         the provisions of this Paragraph 4 will thereafter be applicable as
         nearly as may be in relation to any shares of stock or securities
         thereafter deliverable upon the exercise of this Warrant.

                  (d) NOTICE OF ADJUSTMENT. Upon the occurrence of any event
         that requires any adjustment of the Exercise Price, then, and in each
         such case, the Company shall give notice thereof to the holder, which
         notice shall state the Exercise Price resulting from such adjustment
         and the increase or decrease in the number of Warrant Shares
         purchasable at such price upon exercise, setting forth in reasonable
         detail the method of calculation and the facts upon which such
         calculation is based. Such calculation shall be certified by
         independent public accountants then engaged by the Company.

                  (e) MINIMUM ADJUSTMENT OF EXERCISE PRICE. No adjustment of the
         Exercise Price shall be made in an amount of less than 1% of the
         Exercise Price in effect at the time such adjustment is otherwise
         required to be made, but any such lesser adjustment shall be carried
         forward and shall be made at the time and together with the next
         subsequent adjustment which, together with any adjustments so carried
         forward, shall amount to not less than 1% of such Exercise Price.

                  (f) NO FRACTIONAL SHARES. No fractional shares of Common Stock
         are to be issued upon the exercise of this Warrant, but the Company
         shall pay a cash adjustment in respect of any fractional shares which
         would otherwise be issuable in an amount equal to the same fraction of
         the Market Price (as defined herein) of a share of Common Stock on the
         date of such exercise.

                  (g) OTHER NOTICES. In case:

                           (i) the Company shall declare any dividend upon the
                  Common Stock payable in shares of stock of any class or make
                  any other distribution (including dividends or distributions
                  payable in cash out of retained earnings) to the holders of
                  the Common Stock;

                           (ii) the Company shall offer for subscription pro
                  rata to the holders of the Common Stock any additional shares
                  of stock of any class or other rights;

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                           (iii) there shall be any capital reorganization of
                  the Company, or reclassification of the Common Stock, or
                  consolidation or merger of the Company with or into or sale of
                  all or substantially all its assets to, another corporation or
                  entity; or

                           (iv) there shall be a voluntary or involuntary
                  dissolution, liquidation or winding-up of the Company;

         then, in each such case, the Company shall give to the holder (a)
         notice of the date on which the books of the Company shall close or a
         record shall be taken for determining the holders of Common Stock
         entitled to receive any such dividend, distribution, or subscription
         rights or for determining the legal holders of Common Stock entitled to
         vote in respect of any such reorganization, reclassification,
         consolidation, merger, sale, dissolution, liquidation or winding up and
         (b) in the case of any such reorganization, reclassification,
         consolidation, merger, sale, dissolution, liquidation or winding-up,
         notice of the date (or, if not then known, a reasonable approximation
         thereof by the Company) when the same shall take place. Such notice
         shall also specify the date on which the holders of Common Stock shall
         be entitled to receive such dividend, distribution, or subscription
         rights or to exchange their Common Stock for stock or other securities
         or property deliverable upon such reorganization, reclassification,
         consolidation, merger, sale, dissolution, liquidation, or winding-up,
         as the case may be. Such notice shall be given at least 30 days prior
         to the record date or the date on which the Company's books are closed
         in respect thereto. Failure to give any such notice or any defect
         therein shall not affect the validity of the proceedings referred to in
         clauses (i), (ii), (iii) and (iv) above.

                  (h) CERTAIN DEFINITIONS:

                           (i) "MARKET PRICE" as of any date, means (a) the
                  average of the last reported sale prices on the principal
                  trading market for the Common Stock for the five trading days
                  immediately preceding the date of any such determination, or
                  (b) if market value cannot be calculated as of such date on
                  the foregoing basis, Market Price shall be the fair market
                  value as reasonably determined in good faith by the Board of
                  Directors of the Company. The manner of determining the Market
                  Price of the Common Stock sets forth in the foregoing
                  definition shall apply with respect to any other security in
                  respect of which a determination as to market value must be
                  made hereunder.

                           (ii) "COMMON STOCK" for the purposes of this
                  Paragraph 4, includes the Common Stock, par value $0.0001 per
                  share, or shares resulting from any subdivision or combination
                  of such Common Stock, or in the case of any reorganization,
                  reclassification, consolidation, or sale of the character
                  referred to in Paragraph 4(c), the stock or other securities
                  or property provided for in such Paragraph.

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         5. ISSUE TAX. The issuance of certificates for Warrant Shares upon the
exercise of this Warrant shall be made without charge to the holder or such
shares for any issuance tax or other costs in respect thereof, provided that the
Company shall not be required to pay any tax that may be payable in respect of
any transfer involved in the issuance and delivery of any certificate in a name
other than the holder of this Warrant.

         6. NO RIGHTS OR LIABILITIES AS A SHAREHOLDER. This Warrant shall not
entitle the holder to any voting rights or other rights as a shareholder of the
Company. No provision of this Warrant, in the absence of affirmative action by
the holder to purchase Warrant Shares, and no mere enumeration herein of the
rights or privileges of the holder, shall give rise to any liability of such
holder for the Exercise Price or as a shareholder of the Company, whether such
liability is asserted by the Company or by creditors of the Company.

         7. TRANSFER AND REPLACEMENT OF WARRANT.

                  (a) RESTRICTION ON TRANSFER. This Warrant and the rights
         granted to the holder are transferable, in whole or in part, upon
         surrender of this Warrant, together with a properly executed assignment
         in the form attached hereto, at the office of the Company referred to
         in Paragraph 7(d) below, provided, however, that any transfer or
         assignment shall be subject to the conditions set forth in Paragraph
         7(e). Until due presentment for registration of transfer on the books
         of the Company, the Company may treat the registered holder as the
         owner and holder of this Warrant for all purposes, and the Company
         shall not be affected by any notice to the contrary.

                  (b) REPLACEMENT OF WARRANT. Upon receipt of evidence
         reasonably satisfactory to the Company of the loss, theft, destruction,
         or mutilation of this Warrant and, in the case of any such loss, theft,
         or destruction, upon delivery of an indemnity agreement reasonably
         satisfactory in form and amount to the Company, or, in the case of any
         such mutilation, upon surrender and cancellation of this Warrant, the
         Company, at its expense, will execute and deliver, in lieu thereof, a
         new Warrant of like tenor.

                  (c) CANCELLATION; PAYMENT OF EXPENSES. Upon the surrender of
         this Warrant in connection with any transfer or replacement as provided
         in this Paragraph 7, this Warrant shall be promptly canceled by the
         Company. The Company shall pay all taxes (other than securities
         transfer taxes) and all other expenses (other than legal expenses, if
         any, incurred by the Holder) in connection with the preparation,
         execution, and delivery of Warrants pursuant to this Paragraph 7.

                  (d) REGISTER. The Company shall maintain, at its principal
         executive offices (or such other office of the Company as it may
         designate by notice to the holder), a register for this Warrant, in
         which the Company shall record the name and address of the person in
         whose name this Warrant has been issued, as well as the name and
         address of each transferee and each prior owner of this Warrant.

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                  (e) EXERCISE OR TRANSFER WITHOUT REGISTRATION. If, at the time
         of the surrender of this Warrant in connection with any exercise,
         transfer, or exchange of this Warrant, this Warrant (or in the case of
         any exercise, the Warrant Shares issuable hereunder) shall not be
         registered under the Securities Act and under applicable state
         securities or blue sky laws, the Company may require, as a condition of
         allowing such exercise, transfer, or exchange (i) that the holder or
         transferee of this Warrant, as the case may be, furnish to the Company
         a written opinion of counsel, which opinion and counsel are reasonably
         acceptable to the Company, to the effect that such exercise, transfer
         or exchange may be made without registration under said Act and under
         applicable state securities or blue sky laws, and (ii) that the holder
         or transferee execute and deliver to the Company an investment letter
         in form and substance acceptable to the Company. The first holder of
         this Warrant, by taking and holding the same, represents to the Company
         that such holder is acquiring this Warrant for investment and not with
         a view to the distribution thereof.

         8. NOTICES. All notices, requests and other communications required or
permitted to be given or delivered hereunder to the holder of this Warrant shall
be in writing, and shall be personally delivered, or shall be sent by certified
or registered mail or by recognized overnight mail courier, postage prepaid and
addressed, to such holder at the address shown for such holder on the books of
the Company, or at such other address as shall have been furnished to the
Company by notice from such holder. All notices, requests, and other
communications required or permitted to be given or delivered hereunder to the
Company shall be in writing, and shall be personally delivered, or shall be sent
by certified or registered mail or by recognized overnight mail courier, postage
prepaid and addressed to the office of the Company at 13135 Dairy Ashford, Suite
525, Sugar Land, Texas 77048, Attention: Chief Executive Officer, or at such
other address as shall have been furnished to the holder of this Warrant by
notice from the Company. Any such notice, request or other communication may be
sent by facsimile, but shall in such case be subsequently confirmed by a writing
personally delivered or sent by certified or registered mail or by recognized
overnight mail courier as provided above. All notices, requests and other
communications shall be deemed to have been given either at the time of the
receipt thereof by the person entitled to receive such notice at the address of
such person for purposes of this Paragraph 8 or, if mailed by registered or
certified mail or with a recognized overnight mail courier upon deposit with the
United States Post Office or such overnight mail courier, if postage is prepaid
and the mailing is properly addressed, as the case may be.

         9. GOVERNING LAW. THIS WARRANT SHALL BE GOVERNED AND CONSTRUED AND
ENFORCED IN ACCORDANCE WITH THE INTERNAL LAWS OF THE STATE OF DELAWARE WITHOUT
REGARD TO THE BODY OF LAW CONTROLLING CONFLICTS OF LAW.

         10. MISCELLANEOUS.

                  (a) AMENDMENTS. This Warrant and any provision it may only be
         amended by an instrument signed by the Company and the holder.

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                  (b) DESCRIPTIVE HEADINGS. The descriptive headings of the
         several paragraphs of this Warrant are inserted for purposes of
         reference only, and shall not affect the meaning or construction of any
         of the provisions of this Warrant.

                  (c) SEVERABILITY AND SAVINGS CLAUSE. If any one or more of the
         provisions contained in this Agreement is for any reason (i) objected
         to, contested or challenged by any court, government authority, agency,
         department, commission or instrumentality of the United States or any
         state or political subdivision thereof, or any securities industry
         self-regulatory organization (collectively, "Governmental Authority"),
         or (ii) held to be invalid, illegal or unenforceable in any respect,
         the Company and the holder agree to negotiate in good faith to modify
         such objected to, contested, challenged, invalid, illegal or
         unenforceable provision. It is the intention of Company and the holder
         that there shall be substituted for such objected to, contested,
         challenged, invalid, illegal or unenforceable provision a provision as
         similar to such provision as may be possible and yet be acceptable to
         any objecting Governmental Authority and be valid, legal and
         enforceable. Further, should any provisions of this Agreement ever be
         reformed or rewritten by a judicial body, those provisions as rewritten
         will be binding, but only in that jurisdiction, on the holder and the
         Company as if contained in the original Agreement. The invalidity,
         illegality or unenforceability of any one or more provisions of this
         Warrant will not affect the validity and enforceability of any other
         provisions of this Warrant.

         WITNESS the signature of a proper officer of the Company as of the date
first above written.

                                        IVG CORP.


                                        /s/ Elorian Landers
                                        ----------------------------------------
                                        Elorian Landers, Chief Executive Officer

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                              [FORM OF ASSIGNMENT]

                   (TO BE EXECUTED BY THE REGISTERED HOLDER IF
            SUCH HOLDER DESIRES TO TRANSFER THE WARRANT CERTIFICATE)


         FOR VALUE RECEIVED, _______________________________________ hereby
sells, assigns and transfers unto



--------------------------------------------------------------------------------
(Please print name, address and taxpayer identification number or social
security number of transferee.)

the accompanying Warrant Certificate, together with all right, title and
interest therein, and does hereby irrevocably constitute and appoint:


--------------------------------------------------------------------------------
attorney, to transfer the accompanying Warrant Certificate on the books of the
Company, with full power of substitution. The transferee's tax identification or
social security number is _____________________.


Dated:                     ,        .
      ---------------------  -------

                                                     [HOLDER]



                                                     By:
                                                        ------------------------
                                                     Name:
                                                          ----------------------
                                                     Title:
                                                           ---------------------


                                     NOTICE


         The signature to the foregoing Assignment must correspond to the name
as written upon the face of the accompanying Warrant Certificate or any prior
assignment thereof in every particular, without alteration or enlargement or any
change whatsoever.

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                         [FORM OF ELECTION TO PURCHASE]

                   (TO BE EXECUTED BY THE REGISTERED HOLDER IF
            SUCH HOLDER DESIRES TO EXERCISE THE WARRANT CERTIFICATE)

To:                                 :
   ---------------------------------

The undersigned hereby irrevocably elects to exercise ____________ of the
Warrants represented by the accompanying Warrant Certificate to purchase the
shares of Common Stock issuable upon the exercise of such Warrants and requests
that certificates for such shares be issued in the name of:

--------------------------------------------------------------------------------
(Please print name and address.)

--------------------------------------------------------------------------------
(Please insert social security or other identifying number.)

The undersigned represents that it is acquiring the shares of Common Stock for
its own account and not with a view to distribution, and it will not sell these
shares unless they have been registered under the Securities Act of 1933 or an
exemption from such registration requirement is available.

If such number of Warrants shall not be all the Warrants evidenced by the
accompanying Warrant Certificate, a new Warrant Certificate for the balance
remaining of such Warrants shall be registered in the name of and delivered to:

--------------------------------------------------------------------------------
(Please print name and address.)

--------------------------------------------------------------------------------
(Please insert social security or other identifying number.)

Dated:                     ,        .
      ---------------------  -------
                                                     ---------------------------
                                                     Holder

                                                     By:
                                                        ------------------------
                                                     Name:
                                                          ----------------------
                                                     Title:
                                                           ---------------------


                                     NOTICE

         The signature to the foregoing Election to Purchase must correspond to
the name as written upon the face of the accompanying Warrant Certificate or any
prior assignment thereof in every particular, without alteration or enlargement
or any change whatsoever.

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