Iowa Admin. Code r. 701-254.2
Employees of the department have official credentials and the taxpayer should require proof of the identity of any person claiming to represent the department. No charges shall be made nor gratuities of any kind accepted by an employee of the department for assistance given in or out of the office of the department.
All employees authorized to collect money are supplied with official receipt forms. When cash is paid to an employee, the taxpayer should require the employee to issue an official receipt. Such receipt shall show the taxpayer's name, address and permit number; the purpose for the payment; and the amount of the payment. The taxpayer should retain all receipts, and only official receipts for a cash payment will be recognized by the department.
This rule is intended to implement Iowa Code sections 453A.25 and 453A.49.
Iowa Admin. Code r. 701-254.2