Money paid by mistake or excess payments shall be refunded, but a mere change of plans after the payment of money, as when a party decides to withdraw an application or to withdraw an appeal, shall not entitle a party to a refund. However, the examination fee shall be refunded if an application is voluntarily withdrawn or abandoned pursuant to § 97.23(a) before the examination has begun. The certificate issuance fee shall be refunded if an application is voluntarily withdrawn or abandoned after an examination has been completed and before a certificate has been issued. Amounts of $1 or less shall not be refunded unless specifically demanded.