Under the ethical requirements of the profession, a certified public accountant may: Retain client records to ensure client payment for work performed Charge a contingent fee for filing an amended tax return in a case where the client had inadvertently omitted a common deduction in the original return Disclose questions from his or her CPA examination Audit a bank where the accountant obtained a current, fully secured 20-year mortgage under the same terms offered to the general public prior to the audit