Plaintiff purchased the property in 1974, and obtained approval for late enrollment of the front building for rent stabilization in 1980. Even though the rear building was not subject to rent stabilization or rent control, there is no indication that the tenant paid more than $500 per month in rent during the remainder of the lease that expired in 1978, or indeed at any time during his continuous occupancy since then. A holdover proceeding by the landlord in 1983 brought a Civil Court ruling that the premises in question were part of a horizontal dwelling unit with the front building, and thus subject to rent stabilization. Dismissal of that proceeding was without prejudice to the landlord’s claim that the tenant was nonetheless illegally occupying part of the premises.