The State Department of Revenue shall charge Calhoun County for collecting the county taxes levied such amount or percentage of total collections as may be agreed upon by the governing body of the county, but such charge shall not in any event exceed 10 percent of the total amount of special county taxes collected hereunder within the county. Such charge for collecting the taxes for the county may be deducted each month from the taxes collected before certifying the amount of the proceeds thereof due Calhoun County for that month. The State Commissioner of Revenue shall pay into the State Treasury all taxes collected under this subpart, as such taxes are received by the Department of Revenue; and on or before the first day of each successive month (commencing with the month following the month in which the department makes the first collections hereunder), the commissioner shall certify to the State Comptroller the amount of taxes collected under the provisions of this subpart and paid by him or her into the State Treasury for the benefit of Calhoun County during the month immediately preceding the making of such certificate. Provided, however, that before certifying the amount of the taxes paid into the State Treasury for the benefit of Calhoun County during each month, the commissioner may deduct from the taxes collected in the month the charges due the department for the collection of the taxes for the county. It shall be the duty of the Comptroller to issue his or her warrant each month payable to the governing body of Calhoun County, in an amount equal to the amount so certified by the State Commissioner of Revenue as having been collected for the use of the county. The custodian of the general funds of Calhoun County shall deposit the revenue derived from the tax levied herein in a special account separate and apart from other funds of the county and such funds shall be used exclusively for the purpose of developing and promoting tourism and conventions. It is hereby further provided that the county and each municipality located in the county shall be authorized to expend revenues generated by the tax imposed herein or other revenues to contract with persons, firms, corporations, or other public or private entities for the exclusive purpose of promoting and developing tourism and conventions in the county and municipalities located therein.