Exhibit 10.21

SECOND AMENDMENT TO  AGREEMENT OF SALE AND PURCHASE(19640 N. 31st Avenue, Phoenix, Arizona)

ThisSECOND AMENDMENT TO AGREEMENT OF SALE AND PURCHASE(this "Amendment") is dated as of
September     , 2002, by and betweenMACK-CALI BEARDSLEY LIMITED PARTNERSHIP,a limited partnership organized under the
laws of the State of Arizona ("Seller"), having an address at c/o Mack-Cali Realty Corporation, 11 Commerce Drive, Cranford, New Jersey
07016 andSUMMIT COMMERCIAL PROPERTIES, INC., a corporation organized under the laws of the State of California
("Purchaser"), having an address at c/o Summit Commercial, 1970 East Grand Avenue, Suite 300, El Segundo, California 90245.

W I T N E S S E T H:

WHEREAS, Seller and Purchaser have entered into a certain Agreement of Sale and Purchase dated as of
July 2, 2002, as amended by that certain First Amendment to Agreement of Sale and Purchase dated as of August 15, 2002 (collectively, the
"Agreement") pursuant to which Agreement Seller agreed to sell and Purchaser agreed to purchase certain Property located at 19640 N. 31st
Avenue, Phoenix, Arizona; and

WHEREAS, Seller and Purchaser have agreed to amend the Agreement as hereinafter set forth.

NOW, THEREFORE, in consideration of the mutual covenants and agreements hereinafter set forth and other good and valuable consideration,
the receipt and sufficiency whereof is hereby acknowledged, intending to be legally bound hereby, the parties hereby agree as follows:

1.    The
"Evaluation Period" as defined in Section 5.1 of the Agreement is hereby extended to 5:00 p.m. Eastern time on September 13, 2002.

2.    All
other terms, conditions and provisions of the Agreement shall continue in full force and effect and unmodified, except to the extent expressly modified hereby.

3.    Capitalized
terms used and not otherwise defined herein shall have the meanings respectively assigned to them in the Agreement.

4.    This
Amendment shall be binding upon and inure to the benefit of the successors, legal representatives, heirs and assigns of the parties hereto.

5.    This
Amendment may be executed by facsimile signatures in any number of counterparts, each of which shall be deemed an original and all of which when considered together
shall be one and the same document.

6.    In
the event of any conflict between the terms of this Amendment and the terms of the Agreement, the terms of this Amendment shall control.

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IN WITNESS WHEREOF, the parties hereto have executed this Amendment as of the day and year first above written.

| |  | SELLER:                                                                                    
| |  | -------------------------------------------------------------------------------------------
| |  | MACK-CALI BEARDSLEY LIMITED PARTNERSHIP
By:    Mack-Cali Sub XXII, Inc. its general partner
| |  | By:                                                                                        
| |  | Name:                                                                                      
| |  | Title:                                                                                     
| |  | PURCHASER:                                                                                 
| |  | SUMMIT COMMERCIAL PROPERTIES, INC.                                                         
| |  | By:                                                                                        
| |  | Name:                                                                                      
| |  | Title:                                                                                     
| |  |                                                                                            

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