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                                                                   Exhibit 10.20

                                OPTION AGREEMENT

          THIS OPTION AGREEMENT (the "AGREEMENT") dated as of February 17, 2000
is made by and between NSP Holdings L.L.C., a Delaware limited liability company
(the "COMPANY") and Robert A. Peterson (the "GRANTEE"), on the other hand.

                              W I T N E S S E T H :

          WHEREAS, the Grantee desires to secure an option (the "OPTION") to
purchase 156,820 Class C Common Units of the Company (the "COMMON UNITS" or the
"UNITS") and the Company is willing to grant such an option on the terms and
subject to the conditions set forth below; and

          WHEREAS, a copy of that certain Limited Liability Company Agreement of
the Company, dated as of February 17, 2000 (as amended, modified, supplemented
or waived from time to time, the "LLC AGREEMENT") has previously been
distributed to the Grantee.

          NOW, THEREFORE, on the basis of the representations, warranties and
covenants set forth herein, the parties hereto agree as follows:

          SECTION 1.   OPTION OF GRANTEE. The Company hereby grants to the
Grantee the irrevocable right and option (the "Option") to subscribe for and
purchase from the Company all of the Common Units, at the exercise price of
$5.89 per Common Unit payable in full upon exercise of the Option (the "Exercise
Price").

          SECTION 2.   EXERCISABILITY; OPTION TERM. The Option shall become
exercisable upon the execution of this Agreement. The term of the Option shall
expire on the tenth anniversary hereof (the "Option Expiration Date").

          SECTION 3.   EXERCISE OF OPTION.

          (a)     The Company shall notify Grantee of the occurrence of all
liquidity events where it might make economic sense for Grantee to exercise the
Option at least twenty days prior to such event. Such notice shall not
constitute a recommendation that Grantee exercise the Option and the Company nor
any affiliate of the Company shall be responsible for any of the consequences
related to Grantee's decision to exercise or not exercise the Option following
any such notice. Grantee shall exercise the Option in full within twenty days
after receipt of the notice from the Company. If the Option is not exercised in
full within twenty days after receipt of such notice, the Option shall be
forfeited by Grantee.

          (b)     The Option may be exercised by the Grantee by giving written
notice to the Company in the manner hereinafter provided specifying their
intention to exercise the Option and

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specifying the date (which shall be not less than ten (10) nor more than thirty
(30) business days after the date of such notice) on which the closing hereunder
shall occur.

          (c)     Each date of a closing hereunder determined pursuant to
Subsection (b) above is herein called a "Closing Date." On each Closing Date,
the Grantee shall deliver to the Company an amount equal to the Exercise Price
multiplied by the number of Units for which the Option is being exercised, in
the form of a bank or cashiers' check or wire transfer to an account previously
designated by the Company, and the Company shall issue and deliver to the
Grantee a certificate or certificates or other evidence of ownership for such
Units in the name of the Grantee.

          SECTION 4.   ADJUSTMENTS FOR MERGER, CONSOLIDATION OR LIQUIDATION.
If, during the term of this Agreement, there shall be a merger or consolidation
of the Company with or into another entity, or the liquidation of the Company,
then, as part of such merger, consolidation or liquidation, lawful provision
shall be made so that the Grantee shall thereafter be entitled to receive on
exercise of the Option, the number of units, other securities or property of the
Company, or of the successor entity resulting from such merger, consolidation or
liquidation to which a holder of the Units deliverable on exercise of the Option
would have been entitled on such merger, consolidation or liquidation. In any
such case, appropriate adjustment (as determined in good faith by the Company's
Board of Managers) shall be made in the application of the provisions of the
Option with respect to the rights and interests of the Grantee after the merger,
consolidation or liquidation so that the provisions of the Option shall be
applicable after that event, as near as reasonably may be, in relation to any
units, other securities or property deliverable after that event on exercise of
the Option.

          SECTION 5.   REPRESENTATIONS OF THE GRANTEE. Grantee represents
that when he or she exercises his Option you shall be purchasing the Units for
his or her own account and not on behalf of others. Grantee understands and
acknowledges that federal and state securities laws govern and restrict
Grantee's right to offer, sell or otherwise dispose of any Units unless the
offer, sale or other disposition thereof is registered under the Securities Act
and state securities laws, or in the opinion of the Company's counsel, such
offer, sale or other disposition is exempt from registration or qualification
thereunder. Grantee agrees that he or she shall not offer, sell or otherwise
dispose of any Units in any manner which would: (a) require the Company to file
any registration statement with the Securities and Exchange Commission (or any
similar filing under state law) or to amend or supplement any such filing or
(b)violate or cause the Company to violate the Securities Act of 1933, as
amended (the "Securities Act"), the rules and regulations promulgated thereunder
or any other state, federal, Canadian or provincial law. Grantee further
understands that the certificates for any Units purchased shall bear such
legends as the Company deems necessary or desirable in connection with the
Securities Act or other rules, regulations or laws.

          SECTION 6.   NO VIOLATION. This Agreement constitutes a valid and
legally binding agreement of the Grantee and neither the execution and delivery
of this Agreement nor the consummation by the Grantee of the transactions
contemplated hereby will conflict with any judgment, decree, statute or
regulation of any governmental authority applicable to the Grantee or

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any contract, commitment, agreement or restriction of any kind to which the
Grantee is a party or by which the Grantee is bound.

          SECTION 7.   NOTICES. Unless notification is given as to a
different address, all notices hereunder shall be in writing and either
delivered in person or mailed by registered mail, return receipt requested,
addressed as follows:

          (a)     If to the Company:

                  NSP Holdings LLC
                  2211 York Road, Suite 215
                  Oak Brook, IL 60523
                  Fax: (630) 572-8715

          (b)     If to the Grantee:

                  Robert A. Peterson
                  11571 Burr Oak Lane
                  Burr Ridge, IL 60525

          SECTION 8.   ASSIGNMENT. No party may assign its rights or
obligations under this Agreement without the prior written consent of the other
parties, with the exception that the Grantee may assign his or her interests
herein to their immediate lineal descendants upon notice to the Company.

          SECTION 9.   GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY AND
CONSTRUED AND ENFORCED IN ACCORDANCE WITH THE LAWS OF THE STATE OF DELAWARE
WITHOUT REGARD TO PRINCIPLES OF CONFLICTS OF LAW.

          SECTION 10.  AMENDMENTS. This Agreement may not be in any way
modified, amended, terminated, extended or discharged except by a written
instrument signed by the Grantee and the Company.

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          IN WITNESS WHEREOF, the parties hereto have duly executed this
Agreement as of the date first set forth above.

                                    NSP HOLDINGS L.L.C.

                                    By:  /s/ David F. Myers, Jr.
                                           -----------------------------------
                                    Name:  David F. Myers, Jr.
                                    Title: Executive Vice President,
                                           Secretary, CFO


                                    GRANTEE:


                                     /s/ Robert A. Peterson
                                    ------------------------------------------
                                    Robert A. Peterson