No law requiring security upon which loans may be made, prescribing the nature, amount or form of such security, prescribing or limiting interest rates upon loans, or prescribing or limiting the period for which loans may be made, shall apply to loans, advances of credit, or purchases of obligations representing loans and advances of credit payment of which is insured or guaranteed by the United States or any agency or instrumentality thereof.
A.R.S. § 44-1206