There shall be a City Auditor who shall be head of the Bureau of Audits and Accounts. The City Auditor shall be appointed by, and be directly responsible to, the Council for an indefinite term of office. At the time of appointment, the City Auditor shall have had a minimum of three years of combined experience in auditing, accounting or fiscal management, with appropriate training and education. The City Auditor shall have charge and custody of all fiscal records of the City; shall pre-audit all City orders for materials and supplies, certifying to the legality of all such orders and designating the fund or appropriation to which each purchase shall be charged, and shall perform such other accounting or auditing functions as directed by the Council.