(1) A governmental unit, for the purpose of aiding and cooperating in the financing, construction, operation, or maintenance of any regional transportation system, has the power:

(a) To sell, lease, loan, donate, grant, convey, assign, transfer, and otherwise dispose to the authority any real or personal property or interests therein;

(b) To enter into agreements with any person for the joint financing, construction, operation, or maintenance of any regional transportation system. Upon compliance with applicable constitutional or charter limitations, the governmental unit may agree to make payments, without limitation as to amount except as set forth in the agreement, from revenues received from one or more fiscal years, to the authority or any person to defray the costs of the financing, construction, operation, or maintenance of a regional transportation system.

(c) To transfer or assign to the authority any contracts that may have been awarded by the governmental unit for construction, operation, or maintenance of any regional transportation system.

(2) To assist in the financing, construction, operation, or maintenance of a regional transportation system, any county, municipality, or special district that is a member of a combination may, by contract, pledge to the authority all or a portion of the revenues it receives from the highway users tax fund or from any other legally available funds. The authority shall apply revenues that it receives pursuant to the pledge to the financing, construction, operation, or maintenance of any regional transportation system. The authority may refuse to accept any revenues that would cause a member of the combination to exceed its allowable fiscal year spending under section 20 of article X of the state constitution and that could result in a refund of excess revenues under said section 20.