(a) The commissioner may enter into agreements with the patient or a
person liable for him pursuant to this chapter to assure the regular
payment of fees.
(b) The commissioner may collect bills not paid within sixty days of
presentment or pursuant to agreement by the enforcement of liens, the
initiation of suit against liable parties to recover amounts due, or the
initiation of suit to enforce an agreement.
(c) An action to collect fees due pursuant to this chapter shall
commence within six years from the accrual of the cause of action. This
cause of action accrues when the fees become due.