; monitoring use of guarantees (1) Limit on outstanding obligations The total amount of outstanding obligations guaranteed on a cumulative basis by the Secretary under this section may not at any time exceed the greater of— (A) $4,500,000,000; or (B) such higher amount as may be authorized to be appropriated to carry out this section for a fiscal year. (2) Monitoring use of guarantees (A) In general The Secretary shall monitor the use of guarantees under this section by participating jurisdictions. (B) Actions to ensure sufficient authority If the Secretary finds under subparagraph (A) that 50 percent of the aggregate guarantee authority under paragraph (1) has been committed, the Secretary may— (i) provide that a unit of general local government that receives a grant under section 211 may not receive more than $35,000,000 in guarantees under this section; or (ii) submit to Congress a request for the enactment of legislation increasing the amount of the aggregate guarantee authority. (j) Purchase of guaranteed obligations by federal financing bank The Federal Financing Bank may not purchase a note or other obligation guaranteed under this section. (k) Imposition of fee or charge The Secretary shall collect fees from borrowers to result in a credit subsidy cost of zero for guaranteeing notes or other obligations under this section. (l) Guarantee of obligations backed by loans (1) Authority The Secretary may, upon such terms and conditions as the Secretary considers appropriate, guarantee the timely payment of the principal of and interest on such trust certificates or other obligations as may be— (A) offered by the Secretary or by any other offeror approved for purposes of this subsection by the Secretary