Before work is done or material furnished, all contracts that exceed one thousand dollars in amount shall be submitted by the board of county commissioners to the prosecuting attorney of the county. If found by him to be in accordance with sections 153.01 to 153.60, inclusive, of the Revised Code, and his certificate to that effect is indorsed thereon, such contracts shall have full effect, otherwise they shall be void.
R.C. §153.44