A landlord may assess a penalty against a residential tenant for late payment of rent for a residential dwelling unit according to this section.
1. Late payment. A payment of rent is late if it is not made within 15 days from the time the payment is due.
2. Maximum penalty. A landlord may not assess a penalty for the late payment of rent which exceeds 4% of the amount due for one month.
3. Notice in writing. A landlord may not assess a penalty for the late payment of rent unless the landlord gave the tenant written notice at the time they entered into the rental agreement that a penalty, up to 4% of one month's rent, may be charged for the late payment of rent.