To assist him in the preparation of the budget, the city manager, or the city clerk and treasurer at the request of the city manager, shall obtain from the head of each office, department or agency detailed estimates of revenues and expenditures needed for that office, department or agency. The city manager shall then prepare the budget and shall submit it to the council for consideration. The council, by resolution, shall adopt the budget with or without change, and the council shall then certify a copy of the financial statement and estimate and file it with the office of the State Auditor and Inspector or such other agency as the State may from time to time direct. Appropriations shall be effective only after they have been determined and adopted in all respects in accordance with the requirements of the law and this charter.