No person shall operate a taxicab or other vehicle kept for hire, or permit the same to be operated, nor shall any license be issued hereunder, until the applicant for a license deposits with the Mayor, with his application, a policy or certificate of liability insurance for each vehicle for which a license is sought, acceptable to and approved by the Mayor, indemnifying the applicant for not less than one hundred thousand dollars ($100,000) for injury to one person, three hundred thousand dollars ($300,000) for injury to more than one person, and fifty thousand dollars ($50,000) property damage in any one accident through the operation of the taxicab. If the policy is cancelled or amended in any way, the company shall immediately notify the Mayor.