The district council may borrow money, on the full faith and credit of the district, to: acquire by purchase or condemnation an easement under § 21–208 of this subtitle to construct a project in or for the district; and complete the project. The money borrowed by the district council for a project shall: bear interest at a rate set by the district council not exceeding 6% per year; be payable semiannually; and be secured by bonds, notes, or other evidence of indebtedness issued by the district council on the full faith and credit of the district. Subject to § 21–212(e)(2) of this subtitle, the bonds, notes, or other evidence of indebtedness issued under this subsection shall: be exempt from State, county, and municipal taxation; mature serially at the times determined by the district council, not to exceed 30 years; be made payable within 30 years after issuance; and be issued under the seal of the county. Notwithstanding §§ 19–205 and 19–206 of this article, the district council may sell the bonds, notes, or other evidence of indebtedness at public or private sale. The governing body of the county shall guarantee the payment of principal of and interest on any bonds issued by the district council under this section. The guaranty shall be endorsed on each bond in the following language: “The payment of interest when due and the principal at maturity is guaranteed by ….. County, Maryland.” Within 20 days after the bonds are ready for endorsement, the endorsement shall be: signed on each bond by the chair of the governing body or the county executive, as applicable; attested to by the clerk of the governing body of the county; and affixed with the county seal.