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                                                                     EXHIBIT 4.3


                               SECURITY AGREEMENT


     THIS SECURITY AGREEMENT (this "Agreement") is effective this 26th day of
March 1999, by and between MARK A. SCHARMANN, an individual ("Lender"), and
CHICAGO MAP CORPORATION, an Illinois corporation ("Borrower").

                                     RECITAL

     Contemporaneously with the execution of this Agreement, Lender shall loan
to Borrower the sum of $100,000, all as more particularly set forth in that
certain Interim Loan Agreement of even date hereof between Borrower and Lender
(the "Interim Loan Agreement"). Borrower shall use all of the proceeds of the
funds loaned to Lender pursuant to the manner specified in the Interim Loan
Agreement. The Lender would not have expended credit to Borrower without the
grant by the Borrower of a security interest in favor of the Lender in the
collateral described below. In order to provide security for the payment of the
promissory note (the "Note"), the performance of certain terms, covenants, and
conditions set forth in the Interim Loan Agreement and the various obligations
represented hereby, Borrower is granting to the Lender a security interest in
and to the collateral hereinafter described. The principal and interest
evidenced by the Note, together with any extensions, modifications, or renewals;
the performance of the covenants and agreements of Borrower contained in the
Interim Loan Agreement, and the obligations of the Borrower under this Agreement
are hereinafter referred to collectively as the "Obligation."

                                    AGREEMENT

     1.   Creation of Security Interest. In consideration of financial
accommodations given, Borrower grants to Lender a security interest in and to
the following described property (hereinafter the "Collateral") to wit:

          (a)  Accounts receivable, meaning any right of the Borrower to payment
     for goods sold or to be sold or for services rendered or to be rendered, no
     matter how evidenced, including accounts, accounts receivable, contract
     rights, general intangibles, purchase orders, notes, drafts, acceptances
     and other forms of obligations and receivables; and

          (b)  A certificate representing 250,000 shares of the common stock of
     Rexford, Inc. (the "Collateral Shares") which Collateral Shares represent a
     portion of the 10,500,000 shares of Rexford, Inc. common stock to be issued
     to Borrower's stockholders under the Agreement and Plan of Reorganization
     (the "Acquisition Agreement") between Rexford, Inc. and the Borrower.


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If at any time the Collateral representing the Security Interest hereby granted
should decline in value or become impaired or for any other reason be deemed by
the Lender to be insufficient to secure the payment of all sums due and
compliance with all obligations created under the Obligation, Borrower agrees,
within 24 hours of demand by Lender, to furnish such additional Collateral as
may be satisfactory to the Lender. Unless otherwise defined, the words used
herein shall have the same meaning given them in the Illinois Uniform Commercial
Code as now adopted and as hereafter amended from time to time.

     2.  Payment of Principal and Interest. The repayment of the indebtedness
evidenced by the Borrower's Note of even date herewith in the principal sum of
$100,000 with interest thereon at one percent 1% per month from and after the
date thereof. The entire amount loaned under the Note is due three (3) months
from the date thereof.

     3.  Application of Payments. Unless applicable law provides otherwise, all
payments received by Lender under the Note shall be applied by Lender first in
payment of interest payable on the Note, next to the principal of the Note, and
last to any other sums secured by this Agreement.

     4.  Escrow of Collateral Shares. Borrower has executed the Escrow Agreement
attached to the Interim Loan Agreement as Exhibit D and incorporated herein by
this reference (the "Escrow Agreement"), that provides for the escrow of the
Collateral Shares until the Loan is paid in full or an event of default by
Borrower as hereinafter provided.

     5.  Ownership of Collateral in General. The Borrower owns all the
Collateral absolutely and no other person shall have any interest in the
Collateral; except (a) as disclosed on the date hereof as a matter of public
record in the proper place for filing notices of encumbrances on the respective
kinds of property so affected; and (b) except as warranted or disclosed in the
Interim Loan Agreement. The Borrower will defend any proceeding which may affect
the title to or the Lender's security interest in any Collateral, and will
indemnify the Lender and hold it harmless from all damages to Lender from any
such claim, including all costs and expenses of the Lender's defense.

     6.  Prior Indebtedness. The Security Interest granted hereby is subordinate
to the following described interests:




       Secured Party                Collateral                     Date Filed
     -----------------             ------------                  --------------




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     7.1  Events of Default. Upon the occurrence and during the continuance of
any one or more of the events hereinafter enumerated, Lender may forthwith or at
any time thereafter during the continuance of any such event, by notice in
writing to Borrower, declare the unpaid balance of the principal and interest
then accrued on the Note to be immediately due and payable, and the principal
and interest shall become and shall be immediately due and payable without
presentation, demand, protest, notice of protest, or other notice of dishonor,
all of which are hereby expressly waived by Borrower, such events being as
follows:

          (a)  Default in the payment of the principal and interest of the Note
     or any portion thereof when the same shall become due and payable, whether
     at maturity as therein expressed, by acceleration, or otherwise, unless
     cured within 10 days after notice thereof by the holder of such Note to
     Borrower;

          (b)  The creditors under any priority secured indebtedness of Borrower
     shall declare the amounts due thereunder to be due and payable following
     default;

          (c)  Default in the due observance or performance of any other
     covenant or obligation contained in the Interim Loan Agreement, this
     Agreement, or the Acquisition Agreement unless observed or performed within
     10 days after notice thereof to Borrower by Lender; provided, if compliance
     is not possible within 10 days, default shall occur upon failure within 10
     days to take steps that will produce compliance as soon as is reasonably
     practicable;

          (d)  Any representation or warranty herein or in the Acquisition
     Agreement made by Borrower proves to have been untrue in any material
     respect as of the date as of which the facts therein set forth were stated
     or certified, and corrective measures, satisfactory to Lender with respect
     thereto shall not have been taken within 10 days after notice thereof to
     Lender; provided, if compliance is not possible within 10 days, default
     shall occur upon failure within 10 days to take steps that will produce
     compliance as is reasonably practicable;

          (e)  Borrower shall file a voluntary petition in bankruptcy or a
     voluntary petition seeking reorganization, or shall file an answer
     admitting the jurisdiction of the court and any material allegations of an
     involuntary petition filed pursuant to any act of Congress relating to
     bankruptcy or to any act purporting to be amendatory thereof, or shall be
     adjudicated bankrupt, or shall make an assignment for the benefit of
     creditors, or shall apply for or consent to the appointment of any receiver
     or trustee for Borrower, or of all or any substantial portion of its
     property, or Borrower shall make an assignment to an agent authorized to
     liquidate any substantial part of its assets;

          (f)  An order shall be entered pursuant to any of Congress relating to
     bankruptcy or to any act purporting to be amendatory thereof approving an

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     involuntary petition seeking reorganization of Borrower, or an order of any
     court shall be entered appointing any receiver or trustee of or for
     Borrower, or any receiver or trustee of all or any substantial portion of
     the property of Borrower, or a writ or warrant of attachment or any similar
     process shall be issued by any court against all or any substantial portion
     of the property of Borrower, and such order approving a petition seeking
     reorganization or appointing a receiver or trustee is not vacated or
     stayed, or such writ, warrant of attachment, or similar process is not
     released or bonded within 60 days after its entry or levy; or

          (g)  The rendering against the Borrower of final judgment for the
     payment of money in excess of $25,000 and failure of the Borrower to appeal
     therefrom (or from the order, decree, or process pursuant to which such
     judgment was granted, passed, entered, or affirmed) and obtain a stay of
     execution thereof within the period prescribed by law for appeal, or to
     have such judgment discharged and satisfied within 60 days after the
     expiration of such period or of the period of any such stay, whichever
     shall later occur.

     7.2  Procedure on Default. Upon the occurrence of an event of default, and
at any time thereafter, Lender may elect to declare the entire Obligation hereby
secured immediately due and payable:

          (a)  In the event of default in the payment of said Obligation when
     due or declared due, Lender, shall have all the rights and remedies of a
     secured party and shall be entitled to avail itself of all such other
     rights and remedies that may now or hereafter exist at law or in equity for
     the collection of the Obligation and the enforcement of the covenants
     herein and the foreclosure of the security interest created hereby and
     resort to any remedy provided hereunder or provided by the Illinois Uniform
     Commercial Code, or by any other law of the State of Illinois, shall not
     prevent the concurrent or subsequent employment of any other appropriate
     remedy or remedies; and

          (b)  The requirement of reasonable notice to Borrower of the time and
     place of any public sale of the security or of the time after which any
     private sale, or any other intended disposition thereof is to be made,
     shall be met if such notice is mailed, postage prepaid, to Borrower at the
     address of such party designated below, at least 30 days before the date of
     any public or private sale or other disposition is to be made.

     7.3  Defaults Upon Prior Indebtedness. Upon the default by Borrower of any
term, covenant, or condition required to be performed by it on any priority
secured indebtedness or the receipt by Borrower from any such priority secured
creditor of notice of any default under such indebtedness, whether or not
repayment of the indebtedness is accelerated. Borrower shall promptly advise
Lender in writing of the nature and amount of default and of the action, if any,
threatened by such priority secured creditor. Notwithstanding the Borrower's
obligation to cure any and all such defaults, Lender may,



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but shall not be obligated to do so, in the name, place and stead of Borrower
and, in the case of such curative efforts by Lender, succeed to all of the
rights, remedies, and security of such priority creditor.

     8.  Cumulative Remedies. The security interest herein granted shall not be
affected by nor affect any other security taken for the indebtedness hereby
secured, or any part thereof, and any extensions may be made of the indebtedness
and this security interest and any releases may be executed, releasing the
Collateral, or any part thereof within effecting the priority of this security
interest or the validity thereof with reference to any third person, and the
holder of said indebtedness shall not be limited by any election of remedies if
he chooses to foreclose this security interest by suit. All remedies provided in
this Agreement are distinct and cumulative to any other right or remedy under
this Agreement or afforded by law or equity, and may be exercised concurrently,
independently, or successively.

     9.  Financing Statement. The Borrower agrees that this Agreement shall also
constitute a financing statement under the Illinois Uniform Commercial Code. If
the Lender shall so request, Borrower shall also execute and deliver a financing
statement on form UCC-1 to further evidence such security interest.

     10. Notices. All notices consents, waivers, and other communications
hereunder shall be in writing and shall be deemed to have been given when sent
by prepaid air mail letter and shall be addressed to each of the parties at its
address first set forth in the Interim Loan Agreement, or at such other address
as may be designated by notice hereunder.

     11. Survival of Warranties and Representations. The representations,
warranties, covenants, agreements, indemnities, and undertakings of the parties
in this Agreement shall not expire with, or be terminated or extinguished by,
the execution and delivery of this Agreement or any document or instrument
contemplated hereby, notwithstanding any investigations of the facts
constituting the basis of the presentations and warranties of another party by
any party hereto or anyone on behalf of any party hereto. Consummation of the
transactions contemplated hereby shall not be deemed or construed as a waiver of
any right or remedy that any party hereto may have or covenant, notwithstanding
any fact or facts that such party knew or should have known at such time.

     12. Severability. In the event of this Agreement or the application of any
such provision to any person or circumstance shall conflict with any
jurisdiction, then such conflict shall not affect any other provision of this
Agreement which can be given effect without the conflicting provision and the
remainder of this Agreement or the application of such provisions to persons or
circumstances other than those as to which such provisions are held invalid or
unenforceable, shall not be affected thereby. The invalidity or unenforceability
of this Agreement or any provisions thereof in any jurisdiction shall not affect
the validity or enforceability of this Agreement or of such provision in any




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other jurisdiction. To this end, the provisions of this Agreement are declared
to be severable. In the event that any law limiting the amount of interest or
other charges permitted to be collected from the undersigned is interpreted so
that any charge provided for in this Agreement, whether considered separately or
together with other charges that are considered a party of this Agreement,
violates such law, and the Borrower declared by a court having jurisdiction in
the premises to be entitled to the benefit of such law, such charge is hereby
reduced to the extent necessary to eliminate such violation. The amounts, if
any, previously paid to the Lender in excess of the amounts payable to the
Lender computed on the basis of such charges as reduced shall be applied by
Lender to reduce the principal of the indebtedness secured by this Agreement.

     13. Modification. This Agreement may not be supplemented, varied, or
rescinded except by a writing which contains an express reference to this
Agreement and which is signed by the party against whom enforcement of the
supplement, variance, or rescission is asserted.

     14. Governing Law. This Agreement is being executed and delivered and is
intended to be performed in, and the execution, validity construction, and
performance of this Agreement shall be construed and enforced in accordance
with, the laws of the State of Illinois.

     IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of
the date first above written.

LENDER:                                     BORROWER:

MARK A. SCHARMANN,                          CHICAGO MAP CORPORATION,
 an Individual                               an Illinois corporation


/s/ Mark A. Scharmann                        /s/ Steven J. Peskaitis
----------------------------------          ------------------------------------
Mark A. Scharmann                           Its Duly Authorized Officer