Before the council’s hearing on the issuance of the license, the chief of police shall investigate the character of the applicant and shall inspect the taxis to be licensed for possible violations of the state motor vehicle law or of this chapter, and shall report on these matters to the council. No taxi shall be in excess of five years of age. All taxi cabs operated under this chapter shall be inspected at least once every 90 days as to lights, brakes, horn, steering, tires, and operating conditions and a certificate of a reputable auto mechanic shall be filed with the city clerk showing that said taxi cabs are in safe operating condition. [Code 1975 § 7-4.05.]