ยง  454.  Servicing  of  municipal  loans  by banking institutions. The
  municipality is  authorized  to  make  provision,  either  in  the  loan
  agreement  or  by separate agreement, for the performance by one or more
  banking institutions of such services as are generally performed by  any
  such  bank  itself owning and holding such a loan and as may be approved
  by the superintendent of financial services, for which services  a  bank
  may  make  and  collect such service charges as the superintendent shall
  prescribe or approve.