All joint vocational school district funds shall be kept in depositories selected pursuant to sections 135.01 to 135.21 of the Revised Code. The treasurer of the joint vocational school district shall be the custodian of such funds. Such funds shall be disbursed only pursuant to warrant signed by such treasurer and a person so authorized by the board of education of the joint vocational school district, and pursuant to order of such board approving such expenditure. No contract of such board of education involving the expenditure of money shall become effective until the fiscal officer of the joint vocational school district certifies there are funds in the treasury and otherwise unappropriated sufficient to provide therefor.