(2)In the case of a commission involving prolonged work, the Court may permit the commissioner to withdraw from time to time such sum as may appear necessary and reasonable on account of fee, travelling expenses, etc. All such payments before the completion of the work shall be subject to the condition that if the commission is found not to have been executed satisfactorily, or if the work turns out to be less than was expected, the commissioner shall refund such sum as may be directed by the Court.
