SECTION 1.   Section 6B. The department shall establish the maximum charges that may be made by persons subject to the provisions of this chapter for the towing away of motor vehicles, when such towing is ordered by the police or other public authority. Notwithstanding any general or special law to the contrary, a city or town by vote of its council or selectmen may establish the maximum rate that may be charged for the towing away of motor vehicles within its jurisdiction, but the maximum rate charged by a city or town shall not exceed the maximum rate established by the department. Persons subject to the provisions of this chapter for the towing away of motor vehicles may charge an additional fee. The calculation for said fee shall include, but not be limited to, the following: wrecker working, winching, waiting time, clean up time and the provisions for special equipment and personnel necessary for placing a disabled vehicle in a position to be towed. The charges for such extraordinary, special or additional services shall not exceed the carriers normal and customary rates charged to similarly situated customers. The maximum rate for said fee shall be on file with the department. Notwithstanding any general or special law to the contrary, a city or town by vote of its council or selectmen may establish the maximum rate that may be charged for the towing away of motor vehicles within its jurisdiction, but the maximum rate charged by a city or town shall not exceed the maximum rate established by the Department.