"Revolving loan account" means an arrangement between a lender and a debtor pursuant to which:
(1) the lender may permit the debtor to obtain loans from time to time;
(2) the unpaid balances of principal and the loan finance and other appropriate charges are debited to an account;
(3) a loan finance charge if made is not precomputed but is computed on the outstanding unpaid balances of the debtor's account from time to time; and
(4) the debtor has the privilege of paying the balances in installments.