(a) If the amount of a late fee and the conditions for imposing a late fee are stated in the rental agreement or in an addendum to the rental agreement, the operator may impose a late fee on the occupant for each month the occupant does not pay rent when due that does not exceed the greater of:
(1) Thirty dollars ($30.00) per month; or
(2) Twenty percent (20%) of the amount of monthly rent.
(b) Expenses incurred as a result of rent collection or lien enforcement by an operator may be charged to the occupant in addition to the late fees permitted by this section.