The authority may at any time issue revenue bonds for the purpose of paying any part of the cost of any project or part thereof. Every issue of its bonds shall be payable out of the revenues of the authority which may be pledged for such payment, without preference or priority of the first bonds issued, subject to any agreement with the holders of any other bonds or pledging any specified revenues. The bonds shall be authorized by resolution of the authority, shall bear such date or dates, and shall mature at such time or times, but not in excess of forty years, as the resolution shall specify. The bonds shall be in such denomination, bear interest at such rate, be in such form, either coupon or registered, be issued in such manner, be payable in such place or places and be subject to redemption as such resolution may provide. The bonds of the authority may be sold at public or private sale, as hereafter provided, at such price or prices as the authority shall determine, but at not less than ninety-five percent of the principal amount thereof and at such interest rate as the authority shall determine. Such bonds shall be sold at public sale or, if the authority determines it is in the best interest of the authority, at private sale. The reason or reasons why private sale is in the best interest of the authority shall be set forth in the order or resolution authorizing the private sale. The decision of the authority shall be conclusive.