The director of the division of finance may from time to time establish such rules and regulations in respect to loans as may be reasonably necessary to assure that such loans are in keeping with sound lending practices and promote the purposes of sections 369.010 to 369.369, and the director may include therein provisions concerning appraisals, payments and terms of security instruments. Any note or security instrument may provide for advances for taxes, insurance premiums and other charges, which may be commingled with other funds of the association, and the extent, if any, to which interest is to be paid thereon.