The term consumer credit means credit extended to a natural person for personal, family, or household purposes, including loans secured by liens on real estate and chattel liens secured by mobile homes and leases of personal property to consumers that may be considered the functional equivalent of loans on personal security: Provided, the savings association relies substantially upon other factors, such as the general credit standing of the borrower, guaranties, or security other than the real estate or mobile home, as the primary security for the loan. Appropriate evidence to demonstrate justification for such reliance should be retained in a savings association's files. Among the types of credit included within this term are consumer loans; educational loans; unsecured loans for real property alteration, repair or improvement, or for the equipping of real property; loans in the nature of overdraft protection; and credit extended in connection with credit cards.