No reimbursement will ordinarily be required from individuals with respect to payments made in their behalf under this part. However, prior to the posting of bail on behalf of a defendant, a signed agreement shall be secured from him wherein he agrees to remit the amount of such bail or permit the application of so much of his pay as may be necessary to reimburse the Government in the event that he willfully causes forfeiture of bail. In the event of such forfeiture, bail provided under this part shall be recovered from the defendant in accordance with that agreement. The agreement should include a statement that it does not prejudice the defendant's right to appeal to the Comptroller General of the United States and the courts after such payment or deduction has been made, if he considers the amount erroneous.