Removal and impounding of vehicles under this Part shall be done only by "approved storage garages" that shall be designated from time to time by the City Council. Every such garage shall submit evidence to the City Council that it is bonded or has acquired liability insurance in an amount satisfactory to the City Council as sufficient to indemnify owners of impounded vehicles against loss or damage to those vehicles while in the custody of the garage keeper for the purpose of towing or storage. The approved storage garage shall submit to the City Council its schedule of charges for towing and storage of vehicles under this Part and, when the schedule is approved by the City Council, those charges shall be adhered to by the approved storage garage; no different schedule of charges shall be demanded of or collected from any person whose vehicle is removed or impounded under this Part by any approved storage garage. The City Council shall delete from its list of approved storage garages any garage that makes any unapproved charge in connection with any vehicle removed or impounded under this Part.