The parties may agree to add to a revolving loan account the unpaid balance of a consumer loan, not made pursuant to revolving loan account, or a refinancing, or consolidation thereof, or the unpaid balance of a consumer credit sale, refinancing or consolidation. For the purpose of this section:
(1) the unpaid balance of a consumer loan, refinancing, or consolidation is an amount equal to the principal determined according to the provisions on refinancing (Section 37-3-205); and
(2) the unpaid balance of a consumer credit sale, refinancing, or consolidation is an amount equal to the amount financed determined according to the provisions on refinancing (Section 37-2-205).