No office, department, institution, board, commission or other
agency of County government shall, during any fiscal year, expend
or contract to expend any money or incur any liability or enter into
any contract which, by its terms, involves the expenditure of moneys
in excess of the amounts appropriated or allotted for that category
of expenditure identified in the Commissioner's budget-approving resolution
for such fiscal year without prior approval of the Board of County
Commissioners. Any such contract shall be voidable at the option of
the County Commissioners.