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                                                                   Exhibit 10.50

                                 PROMISSORY NOTE

U.S. $2,275,000.00                                              February 6, 2006

          FOR VALUE RECEIVED, Cole Operating Partnership II, LP, a Delaware
limited partnership ("Borrower"), hereby promises to pay to the order of Series
C, LLC, a Delaware limited liability company ("Lender"), at the office of Lender
located at 2555 East Camelback Road, Suite 400, Phoenix, AZ 85016, the principal
amount of $2,275,000.00, together with interest on the principal balance
outstanding hereunder, from (and including) the date of disbursement until (but
not including) the date of payment, at a per annum rate equal to the Stated
Interest Rate specified below or, to the extent applicable, the Default Interest
Rate specified below, in accordance with the following terms and conditions:

     1. Contracted For Rate of Interest. The contracted for rate of interest of
the indebtedness evidenced hereby, without limitation, shall consist of the
following:

          (a) The Stated Interest Rate (as hereinafter defined), as from time to
time in effect, calculated daily on the basis of actual days elapsed over a
360-day year, applied to the principal balance from time to time outstanding
hereunder;

          (b) The Default Interest Rate (as hereinafter defined), as from time
to time in effect, calculated daily on the basis of actual days elapsed over a
360-day year, applied to the principal balance from time to time outstanding
hereunder; and

          (c) All Additional Sums (as hereinafter defined), if any.

Borrower agrees to pay an effective contracted for rate of interest which is the
sum of the Stated Interest Rate referred to in Subsection 1(a) above, plus any
additional rate of interest resulting from the application of the Default
Interest Rate referred to in Subsection 1(b) above, and the Additional Sums, if
any, referred to in Subsection 1(c) above.

     2. Stated Interest Rate. Except as provided in Section 3 below, interest
shall accrue on the principal balance outstanding hereunder during each Interest
Period (as hereinafter defined) at the Stated Interest Rate. The Stated Interest
Rate shall be a rate per annum equal to the 1-month LIBOR plus 2.0%. "Interest
Period" means each period commencing on the first day of the calendar month and
ending on the first day of the next succeeding calendar month; provided (i) the
first Interest Period shall commence on the date hereof and (ii) any Interest
Period that would otherwise extend past the maturity date of this Note shall end
on the maturity date of this Note. "LIBOR" means, with respect to each Interest
Period, the rate for U.S. dollar deposits with a maturity equal to the number of
months specified above, as reported on Telerate page 3750 as of 11:00 a.m.,
London time, on the second London business day before such Interest Period
begins, or, in the case of the first Interest Period, the second London business
day before the first day of the calendar month during which such Interest Period
begins (or if not so reported, then as determined by the Lender from another
recognized source or interbank quotation).

     3. Default Interest Rate. The Default Interest Rate shall be the Stated
Interest Rate plus 4.0% per annum. The principal balance outstanding hereunder
from time to time shall bear interest at the Default Interest Rate from the date
of the occurrence of an Event of Default (as hereinafter defined) hereunder
until the earlier of: (a) the date on which the principal balance outstanding
hereunder, together with all accrued interest and other amounts payable
hereunder, are paid in full; or (b) the date on which such Event of Default is
timely cured in a manner satisfactory to Lender, (i) if Borrower is specifically
granted a right to cure such Event of Default in any of the Loan Documents (as
hereinafter defined) or (ii) if no such right to cure is specifically granted,
then Lender, in its sole and absolute discretion, permits such Event of Default
to be cured.

     4. Payment. Accrued interest under this Note shall be due and payable in
consecutive monthly payments, commencing on March 1, 2006, and continuing on the
same day of each month thereafter until the Note is

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paid in full. In any event, the principal balance outstanding hereunder,
together with all accrued interest and other amounts payable hereunder, if not
sooner paid as provided herein or in any of the Loan Documents, shall be due and
payable on December 31, 2006.

     5. Application and Place of Payments. Payments received by Lender with
respect to the indebtedness evidenced hereby shall be applied in such order and
manner as Lender in its sole and absolute discretion may elect. Unless otherwise
elected by Lender, all such payments shall first be applied to accrued and
unpaid interest at the Stated Interest Rate and, to the extent applicable, the
Default Interest Rate, next to the principal balance then outstanding hereunder,
and the remainder to any Additional Sums or other costs or added charges
provided for herein or in any of the Loan Documents. Payments hereunder shall be
made at the address for Lender first set forth above, or at such other address
as Lender may specify to Borrower in writing.

     6. Prepayments. Payments of principal hereof may be made at any time, or
from time to time, in whole or in part, without penalty, provided that all
previously matured interest and other charges accrued to the date of prepayment
are also paid in full. Notwithstanding any partial prepayment of principal
hereof, there will be no change in the due date or amount of scheduled payments
due hereunder unless Lender, in its sole and absolute discretion, agrees in
writing to such change.

     7. Events of Default; Acceleration. The occurrence of any one or more of
the following events shall constitute an "Event of Default" hereunder, and upon
such Event of Default, the entire principal balance outstanding hereunder,
together with all accrued interest and other amounts payable hereunder, at the
election of Lender, shall become immediately due and payable, without any notice
to Borrower:

          (a) Nonpayment of principal, interest or other amounts when the same
shall become due and payable hereunder;

          (b) The failure of Borrower to comply with any provision of this Note;

          (c) The failure of Borrower to comply with any provision of any
document, instrument or agreement executed in connection with the indebtedness
evidenced hereby including, without limitation, the Security Agreement, of even
date herewith, executed by Borrower, as grantor, and Lender, as secured party,
wherein Borrower granted a security interest in all of its right, title and
interest in the limited liability company membership interests of Cole MT Denver
CO, LLC ("Cole MT Denver"), or any other security document executed in
connection with this Note (collectively, the "Loan Documents") if such failure
is not cured within 30 days after written notice by Lender to Borrower, as
applicable;

          (d) The dissolution, winding-up or termination of the existence of
Borrower or Cole MT Denver;

          (e) The calling of a meeting of the creditors of Borrower or Cole MT
Denver or the making by Borrower or Cole MT Denver of an assignment for the
benefit of its creditors; or

          (f) The filing by Borrower or Cole MT Denver of a petition or
application for relief under federal bankruptcy law or any similar state or
federal law.

     8. Additional Sums. All fees, charges, goods, things in action or any other
sums or things of value, other than the interest resulting from the Stated
Interest Rate and the Default Interest Rate, as applicable, paid or payable by
Borrower (collectively, the "Additional Sums"), whether pursuant to this Note,
the Loan Documents or any other document or instrument in any way pertaining to
this lending transaction, or otherwise with respect to this lending transaction,
that, under the laws of the State of Arizona, may be deemed to be interest with
respect to this lending transaction, for the purpose of any laws of the State of
Arizona that may limit the maximum amount of interest to be charged with respect
to this lending transaction, shall be payable by Borrower as, and shall be
deemed to be, additional interest, and for such purposes only, the agreed upon
and "contracted for rate of interest" of this lending transaction shall be
deemed to be increased by the rate of interest resulting from the Additional
Sums. Borrower understands and believes that this lending transaction complies
with the usury laws of the State of

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Arizona; however, if any interest or other charges in connection with this
lending transaction are ever determined to exceed the maximum amount permitted
by law, then Borrower agrees that: (a) the amount of interest or charges payable
pursuant to this lending transaction shall be reduced to the maximum amount
permitted by law; and (b) any excess amount previously collected from Borrower
in connection with this lending transaction that exceeded the maximum amount
permitted by law, will be credited against the principal balance then
outstanding hereunder. If the outstanding principal balance hereunder has been
paid in full, the excess amount paid will be refunded to Borrower.

     9. Waivers. Except as set forth in this Note or the Loan Documents, to the
extent permitted by applicable law, Borrower, and each person who is or may
become liable hereunder, severally waive and agree not to assert: (a) any
exemption rights; (b) demand, diligence, grace, presentment for payment,
protest, notice of nonpayment, nonperformance, extension, dishonor, maturity,
protest and default; and (c) recourse to guaranty or suretyship defenses
(including, without limitation, the right to require the Lender to bring an
action on this Note). Lender may extend the time for payment of or renew this
Note, release collateral as security for the indebtedness evidenced hereby or
release any party from liability hereunder, and any such extension, renewal,
release or other indulgence shall not alter or diminish the liability of
Borrower or any other person or entity who is or may become liable on this Note
except to the extent expressly set forth in a writing evidencing or constituting
such extension, renewal, release or other indulgence.

     10. Costs of Collection. Borrower agrees to pay all reasonable costs of
collection, including, without limitation, attorneys' fees, whether or not suit
is filed, and all costs of suit and preparation for suit (whether at trial or
appellate level), in the event any payment of principal, interest or other
amount is not paid when due. In the event of any court proceeding, attorneys'
fees shall be set by the court and not by the jury and shall be included in any
judgment obtained by Lender.

     11. No Waiver by Lender. No delay or failure of Lender in exercising any
right hereunder shall affect such right, nor shall any single or partial
exercise of any right preclude further exercise thereof.

     12. Governing Law. This Note shall be construed in accordance with and
governed by the laws of the State of Arizona, without regard to the choice of
law rules of the State of Arizona.

     13. Time of Essence. Time is of the essence of this Note and each and every
provision hereof.

     14. Amendments. No amendment, modification, change, waiver, release or
discharge hereof and hereunder shall be effective unless evidenced by an
instrument in writing and signed by the party against whom enforcement is
sought.

     15. Severability. If any provision hereof is invalid or unenforceable, the
other provisions hereof shall remain in full force and effect and shall be
liberally construed in favor of Lender in order to effectuate the other
provisions hereof.

     16. Binding Nature. The provisions of this Note shall be binding upon
Borrower and the heirs, personal representatives, successors and assigns of
Borrower, and shall inure to the benefit of Lender and any subsequent holder of
all or any portion of this Note, and their respective successors and assigns.
Lender may from time to time transfer all or any part of its interest in this
Note and the Loan Documents, without notice to Borrower.

     17. Notice. Any notice or other communication with respect to this Note
shall: (a) be in writing; (b) be effective on the day of hand-delivery thereof
to the party to whom directed, one day following the day of deposit thereof with
delivery charges prepaid, with a national overnight delivery service, or two
days following the day of deposit thereof with postage prepaid, with the United
States Postal Service, by regular first class, certified or registered mail; (c)
if directed to Lender, be addressed to Lender at the office of Lender set forth
above, or to such other address as Lender shall have specified to Borrower by
like notice; and (d) if directed to Borrower, be addressed to Borrower at the
address for Borrower set forth below Borrower's name, or to such other address
as Borrower shall have specified by like notice.

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     18. Section Headings. The section headings set forth in this Note are for
convenience only and shall not have substantive meaning hereunder or be deemed
part of this Note.

     19. Construction. This Note shall be construed as a whole, in accordance
with its fair meaning, and without regard to or taking into account any
presumption or other rule of law requiring construction against the party
preparing this Note.

     IN WITNESS WHEREOF, Borrower has executed this Note as of the date first
set forth above.

                                        COLE OPERATING PARTNERSHIP II, LP,
                                        a Delaware limited partnership

                                        By: Cole Credit Property Trust II, Inc.,
                                            a Maryland corporation, its
                                            general partner


                                        By: /s/ John M. Pons
                                            ------------------------------------
                                        Name: John M. Pons
                                        Title: Secretary

                                        Address of Borrower:
                                        2555 E. Camelback Road, Suite 400
                                        Phoenix, AZ 85016