No franchise, grant, renewal, extension or amendment shall be valid which does not reserve to the City the right to prescribe the form and manner in which the records and accounts of the public utility shall be kept; and the right to audit, examine and keep copies of such records and accounts and to require from said utility detailed reports at any time relating to the finances, operation, management and ownership of such utility; provided, however, that the form of accounts which the State Public Utilities Commission may prescribe shall be controlling insofar as they may apply, but the Council may prescribe more detailed forms and exact more comprehensive reports than is required or stipulated by said State Commission; nor shall any such franchise, grant, renewal, extension or amendment be valid which does not reserve to the City the right to establish standards of service, prevent unjust discrimination in service or rates, require adequate extension of plant, equipment and service.