On or before September 10 of the year preceding the effective date of a consolidation agreement, the county boards participating in the consolidation agreement shall adopt by joint or concurrent resolution the budget for the portion of the fiscal year in which the consolidation agreement will be effective. As provided in the consolidation agreement, the county boards shall certify to each county clerk the levies or amounts required to be raised by taxation. In the year in which the general election will be held to first elect consolidated county officers, each county board shall, by joint or concurrent resolution and pursuant to the consolidation agreement, (1) fix the salaries of all elected officers, deputies of elected officers, and appointive officers prior to January 15 and (2) adopt, on or before September 10, the budget for the first complete fiscal year that the counties are consolidated and certify to each county clerk the levies or amounts required to be raised by taxation. On or before September 10 of each year for the duration of the consolidation agreement, each county board shall adopt, by joint or concurrent resolution and pursuant to the agreement, the budget for the consolidated function, service, or office and shall certify to each county clerk the levies or amounts required to be raised by taxation.