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                                                                    EXHIBIT 99.8
    
 
                          PACIFIC GULF PROPERTIES INC.
 
                        NOTICE OF GUARANTEED DELIVERY OF
              8.375% CONVERTIBLE SUBORDINATED DEBENTURES DUE 2001
 
   
     This form, or a form substantially equivalent to this form, must be used to
accept the Exchange Offer (as defined below) if the 8.375% Convertible
Subordinated Debentures Due 2001 (the "Debentures") of Pacific Gulf Properties
Inc., a Maryland corporation (the "Company") are not immediately available, if
the procedure for book-entry transfer cannot be completed on a timely basis, or
if time will not permit all other documents required by the Letter of
Transmittal to be delivered to the Exchange Agent on or prior to the Expiration
Date (as defined in the Prospectus). Such form may be delivered by hand or
transmitted by mail, or (for Eligible Institutions only) by facsimile
transmission, to the Exchange Agent. See the Prospectus. THE ELIGIBLE
INSTITUTION WHICH COMPLETES THIS FORM MUST COMMUNICATE THE GUARANTEE TO THE
EXCHANGE AGENT AND MUST DELIVER THE LETTER OF TRANSMITTAL, THE DEBENTURES AND
ANY OTHER REQUIRED DOCUMENTS, OR, IN THE CASE OF A BOOK-ENTRY TRANSFER, AN
AGENT'S MESSAGE AND ANY OTHER REQUIRED DOCUMENTS, TO THE EXCHANGE AGENT WITHIN
THE TIME SHOWN HEREIN. FAILURE TO DO SO COULD RESULT IN A FINANCIAL LOSS TO SUCH
ELIGIBLE INSTITUTION.
    
 
                             The Exchange Agent is
                       HARRIS TRUST COMPANY OF CALIFORNIA
 
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<S>                                   <C>                                   <C>
               By Mail:                       By Overnight Courier:                        By Hand:
  Harris Trust Company of California    Harris Trust Company of California    Harris Trust Company of California
 c/o Harris Trust Company of New York  c/o Harris Trust Company of New York  c/o Harris Trust Company of New York
         Wall Street Station                77 Water Street, 4th Floor                  Receive Window
            P.O. Box 1010                       New York, NY 10005                77 Water Street, 5th Floor
       New York, NY 10268-1010                                                        New York, NY 10005
                                            By Facsimile Transmission:
                                         (For Eligible Institutions Only)
                                                  (212) 701-7636
                                                  (212) 701-7637
                                              Confirm by Telephone:
                                                  (212) 701-7624
</TABLE>
 
     DELIVERY OF THIS INSTRUMENT TO AN ADDRESS OTHER THAN AS SET FORTH ABOVE OR
TRANSMISSION OF INSTRUCTIONS VIA A FACSIMILE NUMBER OTHER THAN ONE LISTED ABOVE
WILL NOT CONSTITUTE A VALID DELIVERY.
 
     THIS FORM IS NOT TO BE USED TO GUARANTEE SIGNATURES. IF A SIGNATURE ON A
LETTER OF TRANSMITTAL IS REQUIRED TO BE GUARANTEED BY AN ELIGIBLE INSTITUTION
UNDER THE INSTRUCTIONS THERETO, SUCH SIGNATURE GUARANTEE MUST APPEAR IN THE
APPLICABLE SPACE PROVIDED IN THE SIGNATURE BOX ON THE LETTER OF TRANSMITTAL.
 
Ladies and Gentlemen:
 
   
     The undersigned hereby tenders to Pacific Gulf Properties Inc., a Maryland
corporation (the "Company"), upon the terms and subject to the conditions set
forth in the Company's Prospectus dated December 11, 1996 (the "Prospectus"),
and the related Letter of Transmittal (which together constitute the "Exchange
Offer"), receipt of which is hereby acknowledged, the principal amount of 8.375%
Convertible Subordinated Debentures Due 2001 (the "Debentures") of the Company
noted below, pursuant to the guaranteed delivery procedure set forth in the
Prospectus. This Prospectus amends the Company's prospectus dated November 8,
1996.
    
 
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-------------------------------------------------     -------------------------------------------------
         Principal Amount of Debentures                                 Signature(s)
-------------------------------------------------     -------------------------------------------------
         Certificate Nos. (if available)                           Name(s) (Please Print)
  If Debentures will be tendered by book entry        -------------------------------------------------
                    transfer:                                             (Address)
-------------------------------------------------     -------------------------------------------------
          Name of Tendering Institution                        Area Code and Telephone Number
-------------------------------------------------                       Dated: , 1996
           Account No. at (check one):
</TABLE>
 
[ ] The Depository Trust Company
 
[ ] Philadelphia Depository Trust Company
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               GUARANTEE (NOT TO BE USED FOR SIGNATURE GUARANTEE)
 
     The undersigned, a firm that is a member of a registered national
securities exchange or the National Association of Securities Dealers, Inc. or a
commercial bank or trust company having an office or correspondent in the United
States which is a participant in an approved Signature Guarantee Medallion
Program, guarantees (a) that the above-named person(s) has a net long position
in the Debentures being tendered within the meaning of Rule 14e-4 promulgated
under the Securities Act of 1933, as amended, (b) that such tender of Debentures
complies with Rule 14e-4 and (c) to deliver to the Exchange Agent at one of its
addresses set forth above the Debentures tendered hereby, in proper form for
transfer, or a confirmation of the book-entry transfer of the Debentures
tendered hereby into the Exchange Agent's account at The Depository Trust
Company or Philadelphia Depository Trust Company, together with a properly
completed and duly executed Letter(s) of Transmittal (or facsimile(s) thereof),
with any required signature guarantee(s), or, in the case of a book-entry
transfer, on Agent's Message, and any other required documents, all within three
(3) business days after the date hereof.
 
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<S>                                                 <C>

--------------------------------------------------  --------------------------------------------------
                   Name of Firm                                    Authorized Signature

--------------------------------------------------  --------------------------------------------------
                     Address                                       Name (Please Print)

--------------------------------------------------  --------------------------------------------------
              City, State, Zip Code                                       Title

--------------------------------------------------
          Area Code and Telephone Number
</TABLE>
 
Dated:                        , 1996
       ----------------------
 
                     DO NOT SEND DEBENTURES WITH THIS FORM.
          YOUR DEBENTURES MUST BE SENT WITH THE LETTER OF TRANSMITTAL.