Before any claim against any municipality for any property or services for which it is liable is allowed, an itemized invoice accompanied by a voucher verified by the appropriate municipal official that the services, other than those provided by municipal employees, or materials have been received. The invoice and voucher required by this section shall be filed in the office of the municipal finance officer. However, the governing body of any municipality may authorize the prepayment of claims against the municipality for services before they have been provided if the municipality has adopted an ordinance in advance that specifies the maximum amount allowable for any such prepayment and if a service contract exists.
SDCL 9-23-1