B.
The court may determine the fair value of the use and occupancy of the dwelling unit by the tenant from the date when the landlord received actual notice of the condition until such time as the condition is repaired, and further declare what, if any, moneys the tenant owes the landlord or what, if any, rebate the landlord owes the tenant for rent paid in excess of the value of use and occupancy. In making this determination, there shall be a rebuttable presumption that the rental amount equals the fair value of the dwelling unit free from any condition rendering it unfit for human habitation. A written agreement whereby the tenant accepts specified conditions which may violate the warranty of fitness for human habitation in return for a stated reduction in rent or other specified fair consideration shall be binding on the tenant and the landlord. [PL 1977, c. 696, §164 (AMD).]