(1) An RLA loan shall:

(a) provide for complete amortization at maturity through substantially equal monthly payments of principal and interest;

(b) have a term not to exceed 30 years; and

(c) bear interest at an annual rate:

(i) not less than 2% for a project that is for households of 30% or less of median income in the area;

(ii) not less than 3% for a project that is for households between 31% and 50% of median income in the area;

(iii) not less than 4% for a project that is for households between 51% and 80% of median income in the area;

(iv) not less than 6% for a project that is for households between 81% and 95% of median income in the area; and

(v) a rate blended from those rates provided for in (1) (c) (i) , (ii) , (iii) and (iv) for a project that contains units for different area median income household groups.

(d) be subject to a late charge of 4% of the monthly payment due for each monthly payment that is not made within 15 days of its due date; and

(e) will be secured by a lien (perfected either by a mortgage or a trust indenture) against the real property benefited by the loan.