<PAGE>
                                                                     EXHIBIT 4.2

THIS CERTIFICATE IS A GLOBAL CERTIFICATE WITHIN THE MEANING OF THE
PURCHASE/PLACEMENT AGREEMENT (AS DEFINED ON THE REVERSE HEREOF) AND IS
REGISTERED IN THE NAME OF THE CLEARING AGENCY OR A NOMINEE THEREOF. THIS
CERTIFICATE MAY NOT BE EXCHANGED IN WHOLE OR IN PART FOR A CERTIFICATE
REGISTERED, AND NO TRANSFER OF THIS CERTIFICATE IN WHOLE OR IN PART MAY BE
REGISTERED, IN THE NAME OF ANY PERSON OTHER THAN SUCH CLEARING AGENCY OR A
NOMINEE THEREOF, EXCEPT IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE
PURCHASE/PLACEMENT AGREEMENT.

UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE
DEPOSITORY TRUST COMPANY (55 WATER STREET, NEW YORK, NEW YORK) TO THE COMPANY OR
ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE
ISSUED IS REGISTERED IN THE NAME OF CEDE & CO., OR SUCH OTHER NAME AS REQUESTED
BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, AND ANY PAYMENT
HEREON IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN
AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, ANY TRANSFER, PLEDGE
OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL SINCE
THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE OR IN PART FOR CERTIFICATES IN
DEFINITIVE REGISTERED FORM IN THE LIMITED CIRCUMSTANCES REFERRED TO IN THE
PURCHASE/PLACEMENT AGREEMENT, THIS GLOBAL CERTIFICATE MAY NOT BE TRANSFERRED
EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY OR BY A
NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY OR ANOTHER NOMINEE OF THE DEPOSITARY
OR BY THE DEPOSITARY OR ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITARY OR A NOMINEE
OF SUCH SUCCESSOR DEPOSITARY.

THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE U.S. SECURITIES ACT OF 1933, AS
AMENDED (THE "SECURITIES ACT'"), AND MAY NOT BE OFFERED, SOLD, OR PLEDGED EXCEPT
AS SET FORTH BELOW. BY ITS ACQUISITION HEREOF, THE HOLDER (1) REPRESENTS THAT
(A) IT IS A "QUALIFIED INSTITUTIONAL BUYER" (AS DEFINED IN RULE 144A UNDER THE
SECURITIES ACT), (B) IT IS AN INSTITUTIONAL "ACCREDITED INVESTOR" (AS DEFINED IN
RULE 501(a)(1), (2), (3), (7) OR (8) UNDER THE SECURITIES ACT), OR (C) HE OR SHE
IS AN INDIVIDUAL "ACCREDITED INVESTOR" (AS DEFINED IN RULE 501(a) (4), (5) OR
(6) UNDER SECURITIES ACT); (2) AGREES THAT HE, SHE OR IT WILL NOT RESELL OR
OTHERWISE TRANSFER THIS SECURITY EXCEPT (A) TO THE ISSUER THEREOF OF ANY
SUBSIDIARY THEREOF, (B) PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER
THE SECURITIES ACT, (C) TO A QUALIFIED INSTITUTIONAL BUYER IN COMPLIANCE WITH
RULE 144A UNDER THE SECURITIES ACT, (D) TO AN ACCREDITED INVESTOR THAT IS
PURCHASING THE UNITS OR UNDERLYING SHARES OF COMMON STOCK OR WARRANTS FOR HIS,
HER OR ITS OWN ACCOUNT, OR FOR THE ACCOUNT OF SUCH AN ACCREDITED INVESTOR, FOR

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INVESTMENT PURPOSES AND NOT WITH A VIEW TO, OR FOR OFFER OR SALE IN CONNECTION
WITH, ANY DISTRIBUTION THEREOF (AND, IF REQUESTED, BASED ON AN OPINION OF
COUNSEL ACCEPTABLE TO US); OR (E) IN A TRANSACTION EXEMPT FROM, OR NOT SUBJECT
TO, THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT; AND (3) AGREES THAT IT
WILL GIVE TO EACH PERSON TO WHOM THIS SECURITY IS TRANSFERRED A NOTICE
SUBSTANTIALLY TO THE EFFECT OF THIS LEGEND. ANY OFFER, SALE OR OTHER DISPOSITION
PURSUANT TO THE FOREGOING CLAUSE (2) (D) OR (E) IS SUBJECT TO THE RIGHT OF THE
CORPORATION TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL, CERTIFICATIONS OR
OTHER INFORMATION ACCEPTABLE TO IT IN FORM AND SUBSTANCE, AND THE FOREGOING
CLAUSE (D) IS SUBJECT TO THE RIGHT OF THE CORPORATION TO REQUIRE THAT THE
TRANSFEROR DELIVER TO IT A LETTER FROM THE TRANSFEREE SUBSTANTIALLY IN THE FORM
OF APPENDIX B TO THE OFFERING MEMORANDUM.

ONLY WHOLE UNITS WILL BE ISSUED AND MAY BE TRANSFERRED. ANY TRANSFER OF
FRACTIONAL UNITS OR THE UNDERLYING COMMON STOCK OR WARRANTS SHALL BE DEEMED TO
BE VOID AND OF NOT LEGAL EFFECT WHATSOEVER. ANY SUCH PURPORTED TRANSFEREE SHALL
BE DEEMED NOT TO BE THE HOLDER OF SUCH UNITS FOR ANY PURPOSE, INCLUDING, BUT NOT
LIMITED TO THE RECEIPT OF DIVIDENDS ON THE COMMON STOCK UNDERLYING THE UNITS,
AND SUCH PURPORTED TRANSFEREE SHALL BE DEEMED TO HAVE NO INTEREST WHATSOEVER IN
SUCH UNITS.

SO LONG AS THESE UNITS ARE "RESTRICTED SECURITIES" (AS SUCH TERM IS DEFINED IN
RULE 144(a)(3) UNDER THE SECURITIES ACT), THE COMPANY AGREES TO MAKE AVAILABLE
TO EACH HOLDER AND EACH PROSPECTIVE PURCHASER OF THE UNITS DESIGNATED BY A
HOLDER, UPON REQUEST, THE INFORMATION REQUIRED TO BE PROVIDED PURSUANT TO RULE
144A(d)(4) UNDER THE SECURITIES ACT.

PRIOR TO THE DATE (I) THE UNITS QUALIFY AS A CLASS OF "PUBLICLY OFFERED
SECURITIES," OR (II) THE ISSUER COMPLIES WITH ANOTHER AVAILABLE EXCEPTION UNDER
THE PLAN ASSETS REGULATION ISSUED BY THE DEPARTMENT OF LABOR, THE SALE, TRANSFER
OR DISPOSITION OF THE UNITS OR INTERESTS THEREIN WILL NOT BE PERMITTED UNLESS,
FOLLOWING SUCH SALE, TRANSFER OR DISPOSITION, NO SUCH UNIT OR INTEREST THEREIN
IS HELD BY ANY (I) EMPLOYEE BENEFIT PLAN (AS DEFINED IN SECTION 3(3) OF ERISA),
THAT IS SUBJECT TO TITLE I OF ERISA; (II) PLAN DESCRIBED IN SECTION 4975 OF THE
INTERNAL REVENUE CODE, THAT IS SUBJECT TO SECTION 4975 OF THE INTERNAL REVENUE
CODE; (III) ENTITY WHOSE UNDERLYING ASSETS INCLUDE THE INVESTMENT OF ASSETS BY A
PLAN DESCRIBED IN I OR II IN SUCH ENTITIES; OR ANY (IV) ENTITY THAT OTHERWISE
CONSTITUTES A "BENEFIT PLAN INVESTOR" WITHIN THE MEANING OF THE PLAN ASSETS
REGULATION THAT IS SUBJECT TO TITLE I OF ERISA OR SECTION 4975 OF THE INTERNAL
REVENUE CODE.

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<PAGE>
THE UNITS REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO RESTRICTIONS ON
BENEFICIAL AND CONSTRUCTIVE OWNERSHIP AND TRANSFER FOR THE PURPOSE OF THE
COMPANY'S MAINTENANCE OF ITS STATUS AS A REAL ESTATE INVESTMENT TRUST UNDER THE
INTERNAL REVENUE CODE OF 1986, AS AMENDED (THE "CODE"). SUBJECT TO CERTAIN
FURTHER RESTRICTIONS AND EXCEPT AS EXPRESSLY PROVIDED IN THE ARTICLES OF
INCORPORATION OF THE "COMPANY", (I) NO PERSON MAY BENEFICIALLY OR CONSTRUCTIVELY
OWN SHARES OF THE COMPANY'S COMMON STOCK IN EXCESS OF 9.6% (IN VALUE OR NUMBER
OF SHARES, WHICHEVER IS MORE RESTRICTIVE) OF THE OUTSTANDING SHARES OF COMMON
STOCK OF THE COMPANY UNLESS SUCH PERSON IS AN EXCEPTED HOLDER (IN WHICH CASE THE
EXCEPTED HOLDER LIMIT SHALL BE APPLICABLE); (II) NO PERSON MAY BENEFICIALLY OR
CONSTRUCTIVELY OWN SHARES OF CAPITAL STOCK OF THE COMPANY IN EXCESS OF 9.6% OF
THE VALUE OF THE TOTAL OUTSTANDING SHARES OF CAPITAL STOCK OF THE COMPANY,
UNLESS SUCH PERSON IS AN EXCEPTED HOLDER (IN WHICH CASE THE EXCEPTED HOLDER
LIMIT SHALL BE APPLICABLE); (III) NO PERSON MAY BENEFICIALLY OR CONSTRUCTIVELY
OWN CAPITAL STOCK THAT WOULD RESULT IN THE COMPANY BEING "CLOSELY HELD" UNDER
SECTION 856(H) OF THE CODE OR OTHERWISE CAUSE THE COMPANY TO FAIL TO QUALIFY AS
A REIT; AND (IV) OTHER THAN AS PROVIDED IN THE COMPANY'S ARTICLES OF
INCORPORATION, NO PERSON MAY TRANSFER SHARES OF CAPITAL STOCK IF SUCH TRANSFER
WOULD RESULT IN THE CAPITAL STOCK OF THE COMPANY BEING OWNED BY FEWER THAN 100
PERSONS. ANY PERSON WHO BENEFICIALLY OR CONSTRUCTIVELY OWNS OR ATTEMPTS TO
BENEFICIALLY OR CONSTRUCTIVELY OWN SHARES OF CAPITAL STOCK WHICH CAUSES OR WILL
CAUSE A PERSON TO BENEFICIALLY OR CONSTRUCTIVELY OWN SHARES OF CAPITAL STOCK IN
EXCESS OR IN VIOLATION OF THE ABOVE LIMITATIONS MUST IMMEDIATELY NOTIFY THE
COMPANY. IF ANY OF THE RESTRICTIONS ON TRANSFER OR OWNERSHIP ARE VIOLATED, THE
SHARES OF CAPITAL STOCK REPRESENTED HEREBY WILL BE AUTOMATICALLY TRANSFERRED TO
A TRUSTEE OF A TRUST FOR THE BENEFIT OF ONE OR MORE CHARITABLE BENEFICIARIES. IN
ADDITION, UPON THE OCCURRENCE OF CERTAIN EVENTS, ATTEMPTED TRANSFERS IN
VIOLATION OF THE RESTRICTIONS DESCRIBED ABOVE MAY BE VOID AB INITIO. ALL
CAPITALIZED TERMS IN THIS LEGEND HAVE THE MEANINGS DEFINED IN THE ARTICLES OF
INCORPORATION OF THE COMPANY, AS THE SAME MAY BE AMENDED FROM TIME TO TIME, A
COPY OF WHICH, INCLUDING THE RESTRICTIONS ON TRANSFER AND OWNERSHIP, WILL BE
FURNISHED TO EACH HOLDER OF CAPITAL STOCK OF THE COMPANY UPON REQUEST AND
WITHOUT CHARGE.

THE CORPORATION WILL FURNISH TO ANY STOCKHOLDER, ON REQUEST AND WITHOUT CHARGE,
A FULL STATEMENT OF THE INFORMATION REQUIRED BY SECTION 2-211(B) OF THE
CORPORATIONS AND ASSOCIATIONS ARTICLE OF THE ANNOTATED CODE OF MARYLAND WITH
RESPECT TO THE DESIGNATIONS AND ANY PREFERENCES, CONVERSION AND OTHER RIGHTS,
VOTING POWERS,

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RESTRICTIONS, LIMITATIONS AS TO DIVIDENDS AND OTHER DISTRIBUTIONS,
QUALIFICATIONS, AND TERMS AND CONDITIONS OF REDEMPTION OF THE STOCK OF EACH
CLASS WHICH THE CORPORATION HAS AUTHORITY TO ISSUE AND, IF THE CORPORATION IS
AUTHORIZED TO ISSUE ANY PREFERRED OR SPECIAL CLASS IN SERIES, (I) THE
DIFFERENCES IN THE RELATIVE RIGHTS AND PREFERENCES BETWEEN THE SHARES OF EACH
SERIES TO THE EXTENT SET, AND (II) THE AUTHORITY OF THE BOARD OF DIRECTORS TO
SET SUCH RIGHTS AND PREFERENCES OF SUBSEQUENT SERIES. THE FOREGOING SUMMARY DOES
NOT PURPORT TO BE COMPLETE AND IS SUBJECT TO AND QUALIFIED IN ITS ENTIRETY BY
REFERENCE TO THE CHARTER OF THE CORPORATION (THE "CHARTER"), A COPY OF WHICH
WILL BE SENT WITHOUT CHARGE TO EACH STOCKHOLDER WHO SO REQUESTS. SUCH REQUEST
MUST BE MADE TO THE SECRETARY OF THE CORPORATION AT ITS PRINCIPAL OFFICE OR THE
TRANSFER AGENT.

                                       4
<PAGE>
                            ARBOR REALTY TRUST, INC.

                                      UNITS

No.:  [  ]                                                    CUSIP No.: [   ]
Number of Units:   [   ]

      This Unit Certificate certifies that Cede & Co. is the registered Holder
of the number of Units set forth above, as such number may be increased or
decreased as set forth on the Schedule of Increases or Decreases in Global
Certificate annexed hereto. Each Unit consists of (i) five shares of Common
Stock, par value $0.01 per share (the "Common Stock") of Arbor Realty Trust,
Inc. (the "Company") and (ii) a warrant to purchase one share of Common Stock
pursuant to that certain Warrant Agreement (the "Warrant Agreement"), by and
between the Company and American Stock Transfer & Trust Company (the "Warrant
Agent"). All capitalized terms used herein which are not otherwise defined shall
have the meaning set forth in the Purchase/Placement Agreement (the
"Purchase/Placement Agreement"), by and between the Company and the Initial
Purchaser/Placement Agent named therein, and the Warrant Agreement, as
applicable.

      The Warrants underlying the Units represented hereby may not be exercised
or detached from the Units prior to the Detachment Date (as defined in the
Warrant Agreement). Neither the shares of Common Stock nor the Warrants
underlying the Units represented hereby may be transferred except as part of the
Units prior to the Detachment Date.

      THIS UNIT CERTIFICATE SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE
WITH THE LAWS OF THE STATE OF MARYLAND, WITHOUT REGARD TO CONFLICT OF LAW
PROVISIONS THEREOF.

      Reference is hereby made to the further provisions set forth on the
reverse hereof, which further provisions shall for all purposes have the same
effect as if set forth at this place.

      Unless the certificate of authentication hereon has been executed by the
Authenticating Agent by manual signature, this Unit Certificate shall not be
entitled to any benefit under the Purchase/Placement Agreement or the Warrant
Agreement or be valid or obligatory for any purpose.


                                       5
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      IN WITNESS WHEREOF, the Company has caused this instrument to be duly
executed.

                                  ARBOR REALTY TRUST, INC.




Dated: : July 1, 2003             By:
[SEAL]                               --------------------------------------
                                     Name:
                                     Title: President

-----------------------------
Name:
Title: Secretary



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<PAGE>
              AUTHENTHICATING AGENT'S CERTIFICATE OF AUTHENTICATION

      This is one of the Unit Certificates referred to in the within mentioned
Purchase/Placement Agreement and Warrant Agreement.

                                  American Stock Transfer & Trust Company,
                                  as Authenticating Agent




Dated: July 1, 2003
                                 By:
                                     ---------------------------------------
                                     Authorized Officer





                                       7
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                                    [REVERSE]

      The Warrants represented by this Unit Certificate are part of a duly
authorized issue of Warrants of Arbor Realty Trust, Inc. (the "Company")
expiring 5:00 p.m., New York City time, on the Expiration Date. The Warrants
represented hereby are issued pursuant to and are subject in all respects to the
terms and conditions set forth in the Warrant Agreement (the "Warrant
Agreement"), by and between the Company and American Stock Transfer & Trust
Company (the "Warrant Agent"), which Warrant Agreement and any amendments
thereto are hereby incorporated by reference in and made a part of this
instrument, and to which reference is hereby made for a description of the
respective rights, limitations of rights, obligations, duties and immunities
thereunder of the Company, the Warrant Agent and the Holders of Warrants. A copy
of the Warrant Agreement may be obtained from the Company at 333 Earle Ovington
Boulevard, Suite 900, Uniondale, New York 11553, Attention: Frederick C. Herbst,
or the Warrant Agent at American Stock Transfer & Trust Company, 59 Maiden Lane,
Plaza Level, New York, NY 10038, Attention: Corporate Department, by a written
request from the Holder hereof or which may be inspected by any Holder or such
Holder's agent at the principal office of the Company or the Warrant Agent.

      The Common Stock and Warrants underlying the Units represented hereby are
entitled to the benefits of a Registration Rights Agreement dated as of July 1,
2003.

      Prior to the exercise of any Warrant represented hereby, the holder of a
Warrant shall not be entitled to any rights of a stockholder of the Company by
reason of such Person being a holder of any Warrant represented hereby,
including, without limitation, the right to vote or to receive dividends or
other distributions, and shall not be entitled to receive any notice of any
proceedings of the Company, except as provided in the Warrant Agreement.

      The Warrant Agreement permits, with certain exceptions as therein
provided, the amendment thereof and the modification of the rights and
obligations of the Company and the rights of the holders of Warrants under the
Warrant Agreement at any time by the Company and the Warrant Agent with the
consent of the holders of at least a majority of the Warrants at the time
outstanding. Any such consent shall be conclusive and binding upon the holders
of the Warrants evidenced hereby, or in exchange hereof or in lieu hereof,
whether or not notation of such consent or waiver is made thereon.
Notwithstanding the immediately preceding sentence, the Warrant Agreement
provides that the consent in writing of each and every holder of Warrants shall
be required for any such modification, supplement or amendment which (a) changes
the Exercise Period (except to extend the expiration of the Exercise Period to a
later date) or increases the Exercise Price, or (b) reduces the percentage of
holders of outstanding Warrants the consent of who is required to modify,
supplement or amend the Warrant Agreement.

      All terms used in this Unit Certificate which are defined in the Warrant
Agreement shall have the meanings assigned to them in the Warrant Agreement.

      Upon registration of transfer of this Unit Certificate, the transferee
shall be bound under the terms of the Purchase/Placement Agreement, and the
Warrant Agreement and the transferor shall be released from the obligations
under the Purchase/Placement Agreement and the Warrant Agreement. The Company
covenants and agrees, and the holders of the Warrants

                                       8
<PAGE>
and Common Stock, by its acceptance hereof, likewise covenants and agrees, to be
bound by the provisions of this paragraph.






                                       9
<PAGE>
                                  ABBREVIATIONS

      The following abbreviations, when used in the inscription on the face of
this instrument, shall be construed as though they were written out in full
according to applicable laws or regulations:

TEN COM -                as tenants in common
UNIF GIFT MIN ACT -      Custodian

                         ------------------------------------
                         (cust)                       (minor)

                         Under Uniform Gifts to Minors Act

                         ------------------------------------
                                     (State)

TEN ENT -                as tenants by the entireties

JT TEN -                 as joint tenants with right of survivorship and
                         not as tenants in common


Additional abbreviations may also be used though not in the above list.





                                       10
<PAGE>
                               FORM OF ASSIGNMENT

      For value received ________________ hereby sell(s), assign(s) and
transfer(s) unto ________________ (Please insert social security or other
identifying number of assignee) the within Units, and hereby irrevocably
constitutes and appoints ____________________ as attorney to transfer the said
Units on the books of the Company, with full power of substitution in the
premises.


Dated:

----------------------------              -------------------------------

----------------------------              -------------------------------


                                          Signature(s)

Signature(s) must be guaranteed by an Eligible Guarantor Institution with
membership in an approved signature guarantee program pursuant to Rule 17Ad-15
under the Securities Exchange Act of 1934.




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