Section 719. Expenses

If a public defender serves more than one county, the
  expenses  of  salaries, maintenance and operation of his office shall be
  shared by the participating counties in accordance with  the  provisions
  of  the  agreement  establishing  the  office.  Expenses  incidental  to
  individual cases shall be paid by the county for which the services were
  rendered. All expenses chargeable to  a  county  hereunder  shall  be  a
  county  charge to be paid upon certification by the county treasurer out
  of an appropriation made for such purposes.