(a) The limitations contained in this part do not apply to any loan of money by a financial institution as defined in § 45-10-102 that:(1) Is made in accordance with applicable law and in the ordinary course of business;(2) Is made on a basis reasonably designed to assure repayment, evidenced by a written instrument, and subject to a payment due date or amortization schedule; and(3) Bears the usual and customary interest rate of the lending institution.(b) An endorsement or guaranty of a loan made pursuant to subsection (a) shall be considered a contribution in the amount of the endorsement or guaranty and shall be subject to the limitations contained in this part. Where the written instrument does not specify the portion of the loan for which the endorser or guarantor is liable, each endorser or guarantor shall be considered to have made a contribution in that proportion of the unpaid balance that each endorser or guarantor bears to the total number of endorsers or guarantors.