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                                                                EXHIBIT 10.12(B)

                                                                    May 31, 2001

CBRE Holding, Inc.
c/o RCBA Strategic Partners, L.P.
909 Montgomery Street
San Francisco, CA  94133

Attention:  Mr. Claus Moller

RE: AMENDMENT TO COMMITMENT LETTER DATED FEBRUARY 23, 2001

Dear Sir:

          Reference is made to the commitment letter dated February 23, 2001
(the "Commitment Letter") pursuant to which DLJ Investment Partners II, L.P.
agreed, subject to the conditions set forth therein, to purchase up to $75.0
million of senior notes of Holdings (as defined in the Commitment Letter in
connection with the Sponsor's acquisition of CB Richard Ellis Services, Inc.
Capitalized terms used herein and not otherwise defined shall have the meanings
given to them in the Commitment Letter.

          The Commitment Letter is hereby amended and modified as follows:

          1.   The amount of the commitment in the Commitment Letter is hereby
               reduced from $75.0 million to $65.0 million and the Takedown
               Equity associated with the commitment is reduced from 2.0% to
               1.867%.

          2.   The amount of the Credit Facilities referenced in the Commitment
               Letter shall be to $325.0 million and as a partial replacement
               proceeds of up to $225.6 million will be raised in the high yield
               debt market.

          In addition to the foregoing, the undersigned hereby agrees that the
terms of the Notes will be substantially the same as the terms of the senior
subordinated notes due 2011 of BLUM CB Corp. ("Holdings") as set forth in the
confidential offering circular dated May 31,
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2001, except for coupon and the following:

          1.   The Notes will be senior obligations of CBRE Holdings, with such
               changes as are customary for a holding company issuance, the
               language of which will be agreed;

          2.   The Notes will contain a lien covenant pertaining to Holdings and
               an appropriate conduct of business covenant, the language of
               which will be agreed;

          3.   Certain of the negative covenants contained in the Notes will
               terminate when the company obtains an investment grade rating
               from both S&P and Moody's for the Notes of Holdings;

          4.   There will be no requirement to give notice to the banks prior to
               acceleration;

          5.   Grace periods for covenants will conform to the high yield
               indenture.

          In addition to the foregoing, as a condition to closing, we will
receive a list of the entities that will initially be "unrestricted
subsidiaries" prior to closing, such list to be reasonably satisfactory to us.

          Except as expressly amended or modified by this amendment, the terms
of the Commitment Letter shall remain in full force and effect.

          Please indicate your acceptance of the terms hereof by signing in the
appropriate space below and returning a copy of this amendment to the
undersigned.


                              Very truly yours,

                              DLJ INVESTMENT FUNDING, INC.

                              By: /s/ Paul Thompson, III
                                  ----------------------
                                  Paul Thompson III
                                  Managing Director
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Accepted and Agreed to as

of the date first above written:

CBRE HOLDING, INC.

By: /s/ Claus J. Moller
   -------------------
   Name: Claus J. Moller
   Title: President