(a) A service plan may be implemented in an area of a municipality that has not authorized the authority’s sales and use tax levy if:
(1) the authorization by the municipality of the authority’s sales and use tax levy, when combined with the rates of all sales and use taxes imposed by other political subdivisions in the municipality, would exceed two percent in any location in the municipality; and
(2) the municipality has entered into an agreement with the authority to provide public transportation services in a public transportation financing area designated under this subchapter in exchange for all or a portion of the tax increment in the area.
(b) An authority described by § 460.252 may enter into an agreement under Subsection (a)(2) only if the board of directors of the authority approves the agreement by an affirmative vote of at least three-fifths of the members described by either § 460.253(1) or (3) and at least one member appointed by the commissioners court.