The city manager, subject to regulations prescribed by the council, shall contract for, purchase, or issue purchase authorizations for all supplies, materials and equipment for offices, departments and agencies of the city. Every contract or purchase exceeding an amount to be established by the council by resolution shall require prior approval of the council and shall be by competitive bid only. The city manager (for all bids under $7,500.00) and the council (for all bids over $7,500.00) may reject all bids and advertise again. The amounts herein designated may be changed by the council by resolution.
Alterations in any contract may be made when authorized by the council upon the written recommendation of the city manager. If the items being purchased have a single source of supply, or if they are being purchased on a state (Oklahoma or other governmental entity) or federal contract, it shall not be necessary to proceed with competitive bidding.