ASSIGNMENT AND ASSUMPTION OF PURCHASE AGREEMENT

THIS ASSIGNMENT AND ASSUMPTION OF PURCHASE AGREEMENT (this “Assignment”) dated
as of December 7, 2007, is made and entered into by and between TRIPLE NET
PROPERTIES, LLC, a Virginia limited liability company (“Assignor”), and NNN
HEALTHCARE/OFFICE REIT LIMA, LLC, a Delaware limited liability company
(“Assignee”), with reference to the following Recitals:

R E C I T A L S

A. Assignor is “Buyer” under that certain Purchase Agreement mutually executed
as of August 14, 2007, by and between Assignor and St. Rita’s Medical Center, an
Ohio nonprofit corporation, as the same may be amended (the “Purchase
Agreement”), wherein Assignor agreed to purchase certain real property commonly
known as 71 Town Square, the Market Street Health Care Condominiums, High Street
Professional Center Condominiums, High Street Professional Center II
Condominiums, 750 High Street Professional Building Condominiums and St. Rita’s
Regional Cancer Center Condominium, as more particularly described in the
Purchase Agreement, on the terms and conditions set forth in the Purchase
Agreement.

B. Assignor desires to assign and transfer to Assignee, and Assignee desires to
assume from Assignor, all of Assignor’s right, title, claim and interest in, to
and under the Purchase Agreement.

NOW, THEREFORE, in consideration of the foregoing Recitals (which are
incorporated herein by this reference) and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged,
Assignor and Assignee hereby agree as follows:

A G R E E M E N T

1. Assignment; Assumption. Assignor hereby assigns and transfers to Assignee all
of Assignor’s right, title, claim and interest as “Buyer” or otherwise in, to
and under the Purchase Agreement. By executing this Assignment, Assignee hereby
accepts such assignment and expressly agrees to assume and be bound by all of
the provisions of the Purchase Agreement from and after the date hereof.

2. Successors and Assigns. This Assignment shall inure to the benefit of, and be
binding upon, the successors, executors, administrators, legal representatives
and assigns of the parties hereto.

3. Counterparts. This Assignment may be executed in any number of counterparts
with the same effect as if all of the parties had signed the same document. All
counterparts shall be construed together and shall constitute one agreement.

[Signatures on next page]

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IN WITNESS WHEREOF, the parties hereto have caused this Assignment to be
executed by their duly authorized representatives as of the date first written
above.

ASSIGNOR:

TRIPLE NET PROPERTIES, LLC,
a Virginia limited liability company

By: /s/ Richard T. Hutton
Name: Richard T. Hutton
Title: Executive Vice President

ASSIGNEE:

NNN HEALTHCARE/OFFICE REIT
LIMA, LLC,

a Delaware limited liability company

By:/s/ Shannon K.S. Johnson
Authorized Signatory

Shannon K. S. Johnson

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