238.242.  Revenue bonds, authorized — procedures, requirements — refunding bonds — tax-exempt status. — 1.  A district may at any time authorize or issue revenue bonds for the purpose of paying all or any part of the cost of any project.  Every issue of such bonds shall be payable out of the revenues of the district and may be further secured by other property of the district which may be pledged, assigned, mortgaged, or a security interest granted for such payment, without preference or priority of the first bonds issued, subject to any agreement with the holders of any other bonds pledging any specified property or revenues.  Such bonds shall be authorized by resolution of the district, and if issued by the district, 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.  Such bonds shall be in such denomination, bear interest at such rate or rates, be in such form, either coupon or registered, be issued as current interest bonds, compound interest bonds, variable rate bonds, convertible bonds, or zero coupon bonds, be issued in such manner, be payable in such place or places and subject to redemption as such resolution may provide notwithstanding the provisions of section 108.170.  The bonds may be sold at either public or private sale, at such interest rates, and at such price or prices as the district shall determine.

  2.  Any issue of district bonds outstanding may be refunded at any time by the district by issuing its refunding bonds in such amount as the district may deem necessary.  Such bonds may not exceed the amount sufficient to refund the principal of the bonds so to be refunded together with any unpaid interest thereon and any premiums, commissions, service fees, and other expenses necessary to be paid in connection with the refunding.  Any such refunding may be effected whether the bonds to be refunded then shall have matured or thereafter shall mature, either by sale of the refunding bonds and the application of the proceeds thereof to the payment of the bonds being refunded or by the exchange of the refunding bonds for the bonds being refunded with the consent of the holder or holders of the bonds being refunded.  Refunding bonds may be issued regardless of whether the bonds being refunded were issued in connection with the same project or a separate project and regardless of whether the bonds proposed to be refunded shall be payable on the same date or different dates or shall be due serially or otherwise.

  3.  If the proposed project is intended to be merged into the state highways and transportation system for future maintenance under the commission's jurisdiction, the district may contract with the commission to assist it in issuing district revenue bonds and refunding bonds.  The district may also contract with the commission to issue commission revenue bonds and refunding bonds and to loan the proceeds thereof to the district.  Such bonds shall be authorized by commission minute and shall be issued subject to conditions applicable to bonds issued by the district but as determined by the commission rather than the district.

  4.  If the proposed project is intended to be merged into a local transportation system for future maintenance under the local transportation authority's jurisdiction, the district may contract with the local transportation authority to assist it in issuing district revenue bonds and refunding bonds.  The district may also contract with the local transportation authority to issue the local transportation authority's revenue bonds and refunding bonds and to loan the proceeds thereof to the district.  Such bonds shall be authorized by the local transportation authority's ordinance or order and shall be issued subject to conditions applicable to bonds issued by the district but as determined by the local transportation authority rather than the district.

  5.  Bonds issued under this section shall exclusively be the responsibility of the district payable solely out of district funds and property provided in sections 238.200 to 238.275 and shall not constitute a debt or liability of the state of Missouri or any agency or political subdivision of the state.  Neither the district, local transportation authority, nor the commission shall be obligated to pay such bonds with any funds other than those specifically pledged to repayment of the bonds.  Any bonds issued by a district, a local transportation authority, or the commission shall state on their face that they are not obligations of the state of Missouri or any agency or political subdivision thereof other than the district.

  6.  Bonds issued under this section, the interest thereon, or any proceeds from such bonds shall be exempt from taxation in the state of Missouri for all purposes except the state estate tax.