(a) The Commissioner of Property and Procurement shall require the dealer of services referred to in section 3019, subsection (a) of this title, to submit a detailed listing of bills which shall be paid on the basis of certification of the certifying officer of the administering department. The Department of Property and Procurement shall furnish each department, agency, office and commission monthly information as to the bills which have been paid with sufficient detailed data to permit the department or agency involved to determine the accuracy of the charges. Any inaccuracies should be reported to the administering department which shall make appropriate adjustments in the next succeeding payment to the dealer.
(b) Upon establishment of such account or accounts and the transfer thereto of appropriations of the various departments and agencies for the services referred to in section 3019, subsection (b) of this title, which may be done on a monthly or quarterly basis, the department or departments administering such account or accounts shall require the appropriate dealers to submit consolidated bills which shall be paid on the basis of certification of the certifying officer of the department administering the account. Such department shall furnish each department and agency monthly information as to the bills which have been paid with sufficient detailed data to permit the department or agency involved to determine the accuracy of the charges. Should a department or agency find that any bill or bills thus paid on a consolidated basis are improper or inaccurate, such department or agency shall immediately notify the department administering the account, which department shall make appropriate adjustments in the next succeeding payment of the dealer involved.