A creditor, including any of its assignees, that enters into consumer credit transactions secured by a mortgage on real estate and which holds funds of a mortgagor in an escrow account for the payment of taxes or insurance premiums, either on its own behalf or on behalf of another mortgagee, shall pay interest on those funds in accordance with Title 9‑B, section 429.   [PL 1987, c. 396, §12 (NEW).]