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Exhibit 10.28

SECOND LOAN AND NOTE MODIFICATION AGREEMENT
(Borrowing Base Revolving Line of Credit)

Extra Space Properties Thirty LLC

        This SECOND LOAN AND NOTE MODIFICATION AGREEMENT (the "Modification") is
made effective as of May 4, 2009 by and between EXTRA SPACE PROPERTIES
THIRTY LLC, a Delaware limited liability company (the "Borrower"), having its
executive offices at c/o Extra Space Storage LLC, 2795 East Cottonwood Parkway,
Suite 400, Salt Lake City, Utah 84121, and BANK OF AMERICA, N.A., a national
banking association (the "Lender"), whose address is Commercial Real Estate
Banking, NV1-119-04-08, 300 S. Fourth Street, 4th Floor, Las Vegas, Nevada
89101.

Recitals

        A.    Lender has extended to Borrower a borrowing base revolving line of
credit (the "Loan") in the maximum principal amount of up to Fifty Million and
No/100 Dollars ($50,000,000.00) pursuant to a Revolving Line of Credit Agreement
(the "Loan Agreement") and evidenced by a Promissory Note (the "Note"), each
dated February 13, 2009. Capitalized terms used herein without definition, shall
have the meanings given to such terms in the Loan Agreement and Note.

        B.    The Loan is secured by, among other things, eleven (11) separate
Security Instruments executed by Borrower or a Permitted Subsidiary for the
benefit of Lender. Each Security Instrument encumbers a separate Property
approved by Lender as a Borrowing Base Property. The Loan Agreement, Note,
Security Instruments and all other agreements, documents, and instruments
securing the Loan and the Note are referred to individually and collectively as
the "Security Documents".

        C.    EXTRA SPACE STORAGE LLC, a Delaware limited liability company (the
"Guarantor"), unconditionally guaranteed Borrower's obligations under the Loan
and Loan Documents pursuant to that certain Guaranty Agreement dated
February 13, 2009 (the "Guaranty").

        D.    The Loan Agreement, the Note, the Security Documents, the
Guaranty, any environmental indemnities, guaranties and all other agreements,
documents, and instruments evidencing, securing, or otherwise relating to the
Loan, as modified in this Modification, are sometimes referred to individually
and collectively as the "Loan Documents". Hereinafter, "Loan Agreement", "Note",
"Security Instrument", "Security Documents", "Guaranty" and "Loan Documents"
shall mean such documents as modified in this Modification.

        E.    Borrower has requested that Lender approve Properties located in
San Pablo, Contra Costa County, California (the "California Property") and in
North Oxford, Worcestor County, Massachusetts (the "Massachusetts Property") as
Borrowing Base Properties. Extra Space of San Pablo LLC, a Delaware limited
liability company and a wholly-owned subsidiary of Borrower ("ES of San Pablo"),
holds a fee simple interest and a leasehold interest in the California Property
and, in connection with approving the California Property as a Borrowing Base
Property, Borrower has also requested that Lender modify the Loan and Loan
Documents to (i) approve ES of San Pablo as a Permitted Subsidiary, (ii) waive
the requirement with respect to the California Property that all Borrowing Base
Properties (other than the Properties described in Schedules 6.10 and 6.11 of
the Loan Agreement) be owned by Borrower and not by a Permitted Subsidiary, and
(iii) waive the requirement with respect to the California Property that
Properties be owned in fee by a Permitted Subsidiary.

        F.     Lender is willing to so modify the Loan and Loan Documents, and
to make other modifications to such documents, subject to the terms and
conditions hereof.

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Agreement

        For good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, Borrower and Lender agree as follows:

        1.    Recitals.    Borrower hereby acknowledges the accuracy of the
Recitals which are incorporated herein by reference.

        2.    Modifications to Loan Documents.    The Loan Documents are
modified as follows:

        2.1    Borrowing Base Properties.    Subject to the terms and conditions
of the Loan Agreement, as modified by this Modification, Lender agrees to
include the California Property and the Massachusetts Property as Borrowing Base
Properties pursuant to the terms and conditions of the Loan Agreement, as
modified hereby.

        2.2    Permitted Subsidiary.    Subject to the terms and conditions of
the Loan Agreement, as modified by this Modification, Lender agrees to include
ES of San Pablo as a Permitted Subsidiary. All references in the Loan Documents
to the term "Permitted Subsidiary" shall be modified to include ES of San Pablo.

        2.3    Waiver.    Borrower acknowledges that the California Property
fails to satisfy (i) the requirement in Section 4.1(b) of the Loan Agreement
that all Borrowing Base Properties (other than the Properties described in
Schedules 6.10 and 6.11 of the Loan Agreement) be owned by Borrower and not by
any Permitted Subsidiary or any other affiliate of Borrower or any third party,
and (ii) the requirement that a Property, as defined in Schedule 1 of the Loan
Agreement, be owned in fee by a Permitted Subsidiary (the "Ownership
Requirements"). Lender hereby waives the failure of the California Property to
satisfy the foregoing Ownership Requirements and agrees that the California
Property may notwithstanding such failure, qualify as a Borrowing Base Property
if it meets all of the other terms, conditions and requirements of the Loan
Documents. This waiver does not apply to the failure of any other Property or
Borrowing Base Property to satisfy the Ownership Requirements at any time. This
waiver also does not apply to the failure of any Property or Borrowing Base
Property, including the California Property, to satisfy any other term,
condition, or covenant of the Loan Agreement, and all other terms and conditions
of the Loan Agreement remain unchanged except as modified herein.

        2.4    Conforming Modifications.    Each of the Loan Documents is hereby
modified to the extent required to be consistent with the terms hereof. Rights
to or interests in any property granted as security in the Loan Documents,
including the Security Instrument, shall remain as security for the obligations
of the Borrower under the Loan Documents.

        2.5    References.    Each reference in the Loan Documents to any of the
Loan Documents shall be a reference to such document as modified herein.

        3.    Consent and Agreement of Guarantor.    As a condition precedent to
the obligations of Lender hereunder and the effectiveness hereof, Borrower
agrees to provide to Lender concurrently with the execution and delivery of this
Modification, a fully executed Consent and Agreement of Guarantor in form and
substance acceptable to Lender in its sole and absolute discretion.

        4.    Fees and Expenses.    

        4.1    Fees and Expenses.    In consideration of Lender's agreements
herein, Borrower has agreed to pay to Lender: (i) all legal fees and expenses
incurred by Lender in connection herewith, (ii) all title endorsement premium
costs incurred by Lender in connection with this Modification; and (iii) all
other costs and expenses incurred by Lender in connection with this Modification
and the extension of the Loan. Borrower acknowledges and agrees that such fees
are fully earned and nonrefundable as of the date this Modification is executed
and delivered by the parties hereto.

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        4.2    Method of Payment.    All fees, costs, expenses and other
payments due hereunder shall be paid by Borrower to Lender on the date of
closing of this Modification or at such later date as such fees, costs, expenses
and other payments are incurred by Lender. Lender may in its discretion,
disburse such fees, costs, expenses and other payments as an advance under the
Loan and Borrower hereby authorizes such disbursement. Borrower acknowledges and
agrees that such fees, costs and expenses are earned and nonrefundable as of the
date of closing of this Modification or such later date.

        5.    Ratification of Loan Documents and Collateral.    

        The Loan Documents are ratified and affirmed by Borrower and shall
remain in full force and effect as modified herein. Any property or rights to or
interests in property granted as security in the Loan Documents shall remain as
security for the Loan and the obligations of Borrower in the Loan Documents.

        6.    Borrower Representations and Warranties.    

        Borrower represents and warrants to Lender:

        6.1   No default or event of default under any of the Loan Documents as
modified herein, nor any event, that, with the giving of notice or the passage
of time or both, would be a default or an event of default under the Loan
Documents as modified herein has occurred and is continuing.

        6.2   There has been no material adverse change in the financial
condition of Borrower or any other person whose financial statement has been
delivered to Lender in connection with the Loan from the most recent financial
statement received by Lender.

        6.3   Each and all representations and warranties of Borrower in the
Loan Documents are accurate on the date hereof.

        6.4   Borrower has no claims, counterclaims, defenses, or set-offs with
respect to the Loan or the Loan Documents as modified herein.

        6.5   The Loan Documents as modified herein are the legal, valid, and
binding obligation of Borrower, enforceable against Borrower in accordance with
their terms.

        6.6   Borrower validly exists under the laws of the State of its
formation or organization, has not changed its legal name as set forth above,
and has the requisite power and authority to execute and deliver this
Modification and to perform the Loan Documents as modified herein. The execution
and delivery of this Modification and the performance of the Loan Documents as
modified herein have been duly authorized by all requisite action by or on
behalf of Borrower. This Modification has been duly executed and delivered on
behalf of Borrower.

        7.    Borrower Covenants.    

        Borrower covenants with Lender that:

        7.1   Borrower shall execute, deliver, and provide to Lender such
additional agreements, documents, and instruments as reasonably required by
Lender to effectuate the intent of this Modification.

        7.2   Borrower fully, finally, and forever releases and discharges
Lender and its successors, assigns, directors, officers, employees, agents, and
representatives from any and all actions, causes of action, claims, debts,
demands, liabilities, obligations, and suits, of whatever kind or nature, in law
or equity of Borrower, whether now known or unknown to Borrower, (i) in respect
of the Loan, the Loan Documents, or the actions or omissions of Lender in
respect of the Loan or the Loan Documents and (ii) arising from events occurring
prior to the date this Modification is executed and delivered by the parties
hereto. Borrower has been advised by its legal counsel, or

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Borrower has made a reasoned and fully informed decision not to be so
represented by counsel, and understands and acknowledges the significance and
consequences of this release, and Borrower expressly consents and agrees that
the releases contained herein shall be given full force and effect according to
each and all of their express terms and provisions including those relating to
unknown and unsuspected claims, demands and causes of action, if any, as well as
those relating to any other claims, demands and causes of action hereinabove
specified.

        7.3   If required by Lender, on or prior to the execution and delivery
of this Modification, Borrower shall have executed and delivered, or caused to
be executed and delivered, to Lender, each in form and substance satisfactory to
Lender, such other documents, instruments, resolutions, subordinations, and
other agreements as Lender may require in its sole discretion.

        7.4   If required by Lender, on or prior to the execution and delivery
of this Modification, Borrower shall have provided to Lender a certified
resolution authorizing this Modification and designating the person or persons
authorized to sign this Modification and any related documents on behalf of
Borrower.

        8.    Execution and Delivery of Agreement by Lender.    

        Lender shall not be bound by this Modification until (i) Lender has
executed and delivered this Modification, (ii) Borrower has performed all of the
obligations of Borrower under this Modification to be performed
contemporaneously with the execution and delivery of this Modification, if any,
(iii) Borrower has paid all fees and costs in accordance with Section 4 hereof,
and (iv) Guarantor has executed and delivered to Lender a form of Consent and
Agreement of Guarantor acceptable to Lender in all respects.

        9.    Integration, Entire Agreement, Change, Discharge, Termination, or
Waiver.    

        The Loan Documents as modified herein contain the complete understanding
and agreement of Borrower and Lender in respect of the Loan and supersede all
prior representations, warranties, agreements, arrangements, understandings, and
negotiations. No provision of the Loan Documents as modified herein may be
changed, discharged, supplemented, terminated, or waived except in a writing
signed by the parties thereto.

        10.    Binding Effect.    

        The Loan Documents, as modified herein, shall be binding upon and shall
inure to the benefit of Borrower and Lender and their successors and assigns and
the executors, legal administrators, personal representatives, heirs, devisees,
and beneficiaries of Borrower; provided, however, Borrower may not assign any of
its rights or delegate any of its obligations under the Loan Documents and any
purported assignment or delegation shall be void.

        11.    Choice of Law.    

        This Modification shall be governed by and construed in accordance with
the laws of the State of Utah, without giving effect to conflicts of law
principles.

        12.    Counterpart Execution.    

        This Modification may be executed in one or more counterparts, each of
which shall be deemed an original and all of which together shall constitute one
and the same document. Signature pages may be detached from the counterparts and
attached to a single copy of this Modification to physically form one document.
Receipt by the Lender of an executed copy of this Modification by facsimile
shall constitute conclusive evidence of execution and delivery of this
Modification by the signatory thereto.

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        13.    USA Patriot Act Notice.    

        Federal law requires all financial institutions to obtain, verify and
record information that identifies each person who opens an account or obtains a
loan. Lender will ask for the Borrower's legal name, address, tax ID number or
social security number and other identifying information. Lender may also ask
for additional information or documentation or take other actions reasonably
necessary to verify the identity of the Borrower, guarantors or other related
persons

[Remainder of Page Intentionally Left Blank]

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        DATED as of the date first above stated.

    BORROWER:
 
 
EXTRA SPACE PROPERTIES THIRTY LLC
a Delaware limited liability company
 
 
By:
 
/s/ KENT W. CHRISTENSEN

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    Name:   Kent W. Christensen     Title:   Manager
 
 
LENDER:
 
 
BANK OF AMERICA, N.A.
a national banking association
 
 
By:
 
/s/ RICKY G. MONROE

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    Name:   Ricky G. Monroe     Title:   Senior Vice President

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QuickLinks

Exhibit 10.28

SECOND LOAN AND NOTE MODIFICATION AGREEMENT (Borrowing Base Revolving Line of
Credit)
Recitals
Agreement