286.043 Limitation on use of funds for discriminatory contract or bid specifications relating to car rental concessions at airports.—No public funds shall be used by a unit of local government for the purpose of promulgating contract or bid specifications relating to car rental concessions at airports which would preclude a corporation authorized to do business in this state from submitting bids or entering into such contracts with such unit of local government. Nothing in this section shall prevent the local government from providing in such specifications a minimum annual guarantee of revenue to be paid to such unit of local government.