Exhibit 10.4

SECOND AMENDMENT TO AGREEMENT OF PURCHASE AND SALE

THIS SECOND AMENDMENT TO AGREEMENT OF PURCHASE AND SALE (this "Amendment") is
made as of the 7th day of May, 2013, between 9022 HERITAGE PARKWAY, LLC, an
Illinois limited liability company (the “Seller”) and RREEF AMERICA L.L.C., a
Delaware limited liability company (the “Buyer”).

W I T N E S S E T H:

WHEREAS, Buyer and Seller entered into that certain Agreement of Purchase and
Sale with an Effective Date of March 28, 2013, as amended by First Amendment to
Agreement of Purchase and Sale dated April 30, 2013 (collectively, the "Sale
Agreement"), pursuant to which Seller has agreed to sell to Buyer certain
property (the "Property") located at 9022 Heritage Parkway, Woodridge, Illinois,
as more particularly described in the Sale Agreement; and

WHEREAS, Buyer and Seller desire to modify the Sale Agreement in certain
respects.

NOW, THEREFORE, for the sum of Ten Dollars ($10.00) and other good and valuable
consideration in hand paid by each party hereto to the other, the receipt and
sufficiency of which are hereby acknowledged, Buyer and Seller hereby agree as
follows:

1.    Definitions. Any capitalized terms not otherwise defined herein shall have
the meaning ascribed to such term as set forth in the Sale Agreement.

2.    Tenant Estoppel. The Estoppel Certificate has been approved by Seller and
the form is attached hereto as Exhibit “A”.

3.    Seventh Amendment. The Seventh Amendment exhibit attached as Exhibit “G”
to the Sale Agreement, is hereby deleted in its entirety and replaced with the
Exhibit “G” attached hereto.

4.    Approval Date. Buyer hereby waives its termination right under
Subparagraph 6(a) of the Sale Agreement. The Approval Date shall be the date
hereof.

5.    Defeasance/Closing. Paragraph 3 of the Agreement is hereby deleted and the
following is substituted therefor:

“The purchase and sale contemplated herein shall be consummated at a closing
(“Closing”) to take place at the offices of Chicago Title Insurance Company, 10
South LaSalle Street, Chicago, Illinois 60603, on the basis of a “New York
Style” closing. The Closing shall occur on May 31, 2012, on or before the close
of business, or at such other

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time as provided in this Agreement or as the parties may agree upon in writing
(the “Closing Date”); provided, however, if either (a) the Estoppel Certificate
or the Seventh Amendment has not been executed and delivered to Seller (or in
escrow with the Title Company) by Tenant by the original Closing Date or (b)
Seller has not completed the Defeasance (as hereinafter defined) by the original
Closing Date, the Closing Date may be extended by Purchaser for up to thirty
(30) days to allow for said deliveries. The Closing shall be effective as of
12:01 A.M. on the Closing Date. Provided, further, at such time that the
Defeasance has been approved by Seller’s lender and may occur, then thereafter,
Purchaser may elect to accelerate the Closing Date to a date specified in
Purchaser’s notice to Seller (but such accelerated date must be at least seven
(7) business days after the date of Purchaser’s notice to Seller and in no event
prior to May 15, 2013). In order to accelerate the Closing Date as provided in
the foregoing sentence, Purchaser must have waived in writing Purchaser’s right
to terminate this Agreement under Section 6(a) of this Agreement and under
Section 7(d), as to any existing Objections, of this Agreement. Notwithstanding
the foregoing, the risk of loss of all or any portion of the Project shall be
borne by Seller up to and including the actual time of the Closing and wire
transfer of the Purchase Price to Seller, and thereafter by Purchaser, subject
to the terms and conditions of Paragraph 16 below.”

6.    Confirmation. Except as specifically set forth herein, all other terms and
conditions of the Sale Agreement shall remain unmodified and in full force and
effect, the same being confirmed and republished hereby. To the extent there is
any conflict between the terms of this Amendment and the Sale Agreement, the
terms of this Amendment shall control.

7.    Counterparts. This Amendment may be executed in any number of
counterparts, each of which shall be deemed an original, and all of which, when
taken together, shall constitute one and the same instrument. Delivery of a
facsimile or “.pdf” copy of this Amendment executed by a party hereto shall be
deemed to constitute delivery of an original hereof executed by such party.

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IN WITNESS WHEREOF, each of Buyer and Seller has caused this Amendment to be
executed by persons duly authorized thereunto as of the day and year first above
written.

SELLER
9022 HERITAGE PARKWAY, LLC,
an Illinois limited liability company
 
 
By:
9022 HERITAGE PARKWAY MANAGER, LLC,
 
an Illinois limited liability company, its manager
 
 
By:
OAK REALTY GROUP, INC.,
 
an Illinois corporation, its manager
 
 
By:
/s/ Adam M. Levine
Name:
Adam M. Levine
Title:
President

BUYER
RREEF AMERICA L.L.C.,
a Delaware limited liability company
 
 
By:
/s/ Bradley J. Gries
Name:
Bradley J. Gries
Title:
Director