§ 204. Appointment of supervising agency. The local legislative body of a city is hereby authorized by general ordinance or local law to appoint, establish or designate the chief financial officer of the city or some other official or bureau, commission or agency as the person or body to exercise the powers and perform the duties held by or incumbent upon a supervising agency pursuant to this article, except that if there is a board of estimate in the city no such appointment, establishment or designation shall be made and the board of estimate shall exercise such powers and perform such duties or may delegate one or more of them to the chief financial officer of the city or to some other official, bureau, commission or agency.