Revenue bonds issued pursuant to the provisions of sections 99.875 to 99.912 shall be of such denomination, shall bear such rate or rates of interest not to exceed fourteen percent per annum, and shall mature at such time or times, not exceeding thirty-five years from their date of issue, as determined by the governing body of the municipality in its ordinance directing the issuance of the bonds. The bonds may be either serial bonds or term bonds and may be issued with or without reservation of the right to call them for payment or redemption in advance of their maturity, upon the giving of notice, and with or without a covenant requiring the payment of a premium in the event of a call for redemption prior to maturity. The bonds may be sold at such price or prices as the issuing municipality shall determine, but at not less than ninety-four percent of the principal amount thereof. Such bonds shall be sold at public sale, or at private sale if the governing body of the municipality determines it is in the best interest of the issuing municipality to sell the bonds at private sale. The reason or reasons that private sale is in the best interest of the issuing municipality shall be set forth in the ordinance authorizing the private sale. The decision of the governing body of the municipality shall be conclusive.