; and (B) for carrying out the mortgage insurance obligations of the FHA pursuant to section 662(1) and paragraph (1) of this section; and (3) the FHA may exercise any authority of the FHA under this title. (b) Termination of Secretary of HUD’s FHA Authority After the expiration of the transition period under section 551, the Secretary of Housing and Urban Development may not exercise any authority under the National Housing Act relating to mortgage insurance. This subsection may not be construed to limit or otherwise affect the Secretary’s authority under title I of the National Housing Act ( 12 U.S.C. 1702 et seq.). (c) Continuation of Obligations This section and section 552(1) may not be construed to affect the validity of any right, duty, or obligation of the United States or other person arising under or pursuant to any commitment or agreement lawfully entered into with the Secretary of Housing and Urban Development under the National Housing Act . 202. Eligible single-family mortgages (a) In General Notwithstanding section 203 of the National Housing Act ( 12 U.S.C. 1709 ) or any other provision of law, the FHA may insure, and make commitments to insure, a mortgage on a 1- to 4-family residential property only if the mortgage complies with the following requirements: (1) Mortgage amount The mortgage shall involve a principal obligation (including such initial service charges, appraisal, inspection, and other fees as the FHA shall approve) in an amount not to exceed the following amounts: (A) Appraised value 100 percent of the appraised value of the property. (B) Area limitation (i) Maximum limit The lesser of the following amounts: (I) In the case of— (aa) a 1-family residence, 100 percent of the median 1-family house price in the area in which such residence is located, as determined by the FHA