LLS LITTON LOAN SERVICING [GRAPHIC OMITTED]
                                                         4828 Loop Central Drive
                                                                Houston TX 77081
                                                         Telephone  713-966-8966
                                                               Fax  713-218-4595
                                                              www.littonloan.com

March 7, 2007


GMAC/RFC
Attention: Compliance, Servicer Management
2255 North Ontario Street, Suite 400
Burbank, CA 91504-3120

RE:     Mortgage Asset-Backed Pass-Through Certificates, Series 2006-SP4

Dear Sir or Madam:

Enclosed please find the following  required documents for Litton Loan Servicing
LP's annual compliance, year ending December 31, 2006:

              1.  Report on  Compliance  with  Regulation  AB  Criteria
              2.  Deloitte & Touche Attestation on Compliance with Regulation AB
              3.  Servicer  Certification
              4.  Servicer Compliance Statement

We do have  exceptions in our Report on Compliance  with  Regulation AB Criteria
and those will need to be included in the 10K.

We have also emailed a pdf file of each of the above, as well as a Word file for
each. Let me know if you have any questions.

Sincerely,



Elizabeth Folk
Senior Vice President and
Chief Financial Officer



Inv 338(d)-RFC
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                          SERVICER COMPLIANCE STATEMENT

        Mortgage Asset-Backed Pass-Through Certificates, Series 2006-SP4

The  undersigned  officer  of Litton  Loan  Servicing  LP  provides  the  Annual
Statement as to Compliance  as required by the Pooling and  Servicing  Agreement
for the  above  referenced  security  and  certifies  that (i) a  review  of the
activities of the Servicer during such preceding  calendar year (or such shorter
period in the case of the first  such  report)  and of  performance  under  this
Agreement  has  been  made  under  my  supervision,  and  (ii) to the best of my
knowledge,  based on such review, the Servicer has fulfilled all its obligations
under this  Agreement  in all material  respects  for 2006,  except as disclosed
below:

Reconciliations   for   Asset-Backed   Securities   Related   Bank   Account   -
1122(d)(2)(vii)(D)

    Our investor bank account reconciliations included certain reconciling items
    that  were  not  resolved   within  90  calendar  days  of  their   original
    identification   on   eleven   of   sixty-three    investor   bank   account
    reconciliations  selected for testing.  The sum of the reconciling items for
    those eleven reconciliations was $216,950.

Adjustments   to  Interest   Rates  for  Pool  Assets  With  Variable   Rates  -
1122(d)(4)(ix)

    Our testing of sixty-five  adjustable rate mortgages  revealed two instances
    where certain adjustable rate mortgages for which the interest rate reset in
    the  servicing  system did not agree to  interest  rates in the  appropriate
    source index per the  borrower's  note  documents.  These were the result of
    incorrect  information  transferring from the prior servicer.  Additionally,
    the same  sixty-five  mortgages  selected for testing  included one instance
    where the  adjustable  rate  mortgage  payment  change date in the servicing
    system did not agree to the loan documents.

Loss Mitigation Actions - 1122(d)(4)(vii)

    Our testing  disclosed  two  instances  for which there was no evidence that
    approval was obtained for repayment plans,  that were longer than 12 months,
    in accordance with the master servicing guide.


Date:   February 27, 2007

                                       /s/ Elizabeth Folk
                                       Senior Vice President and
                                       Chief Financial Officer
                                       Litton Loan Servicing LP


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                                  CERTIFICATION

        Mortgage Asset-Backed Pass-Through Certificates, Series 2006-SP4

The  undersigned,  a duly  authorized  officer of, Litton Loan Servicing LP (the
"Company"),  as Servicer for Residential  Funding Company,  LLC (the "Sponsor"),
does hereby certify to the Depositor and the Master Servicer and their officers,
with the knowledge and intent that they will rely upon this certification, that:

(1)     I have  reviewed  the  servicer  compliance  statement  of  the  Company
        provided in accordance with Item 1123 of Regulation AB (the  "Compliance
        Statement"),  the report on assessment of the Company's  compliance with
        the  servicing  criteria set forth in Item 1122(d) of Regulation AB (the
        "Servicing  Criteria"),  provided in  accordance  with Rules  13a-18 and
        15d-18 under Securities  Exchange Act of 1934, as amended (the "Exchange
        Act") and Item 1122 of Regulation AB (the "Servicing  Assessment"),  the
        registered  public  accounting  firm's  attestation  report  provided in
        accordance  with  Rules  13a-18 and 15d-18  under the  Exchange  Act and
        Section  1122(b) of Regulation AB (the  "Attestation  Report"),  and all
        servicing reports, officer's certificates and other information relating
        to the servicing of the Mortgage  Loans by the Company  during 2006 that
        were  delivered  by the  Company  to the  Sponsor,  Depositor  or Master
        Servicer pursuant to the applicable  servicing agreement  (collectively,
        the "Company Servicing Information");

(2)     Based on my knowledge,  the Company  Servicing  Information,  taken as a
        whole,  does not contain any untrue statement of a material fact or omit
        to state a material fact necessary to make the  statements  made, in the
        light of the  circumstances  under which such  statements were made, not
        misleading  with  respect to the period of time  covered by the  Company
        Servicing Information;

(3)     Based on my knowledge, all of the Company Servicing Information required
        to be provided by the Company under the relevant servicing agreement has
        been provided to the Depositor, the Sponsor or the Master Servicer;

(4)     I am responsible  for reviewing the activities  performed by the Company
        as servicer under the applicable  servicing  agreement,  and based on my
        knowledge  and  the  compliance   review   conducted  in  preparing  the
        Compliance   Statement  and  except  as  disclosed  in  the   Compliance
        Statement,  the Servicing  Assessment  or the  Attestation  Report,  the
        Company has fulfilled its  obligations  under the  applicable  servicing
        agreement in all material respects; and

(5)     Each  Servicing  Assessment of the Servicer and its related  Attestation
        Report  required to be  included in the Annual  Report by the Company in
        accordance  with Item 1122  Regulation  AB and exchange Act Rules 13a-18
        and  15d-18  has been  provided  to the  Sponsor,  Depositor  or  Master
        Servicer.  Any material instances of non-compliance are described in any
        such Servicing Assessment or Attestation Report.

Date:   February 27, 2007

                                       /s/ Elizabeth Folk
                                       Senior Vice President and
                                       Chief Financial Officer
                                       Litton Loan Servicing LP


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