Each prosecuting attorney may be empowered by the board of county commissioners of his county to appoint deputy prosecuting attorneys upon a finding by such board of county commissioners that such appointments are necessary for the proper conduct of his office. The deputy prosecuting attorneys shall receive a salary to be fixed by the board of county commissioners of his county. The salary of any deputy prosecuting attorney shall be paid monthly from the county treasury on warrants of the county auditor on being allowed and audited by the board of county commissioners, as other claims against the county. Every deputy prosecuting attorney must possess the qualifications required of prosecuting attorneys, except that of county residency.