Types Of Buildings: Prewar Building: A building built before World War II. Postwar Building: A building built after World War II. Brownstone/Townhouse: Previously one-family homes with four or five stories. Many brownstones and townhouses are now multiple-unit apartment buildings (many have ten studio or one-bedroom units). The units can be extremely small but also extremely charming with original moldings from the time of construction (from the 1800s through the early 1900s). These buildings will not have a doorman and most likely no elevator. Walkup Building: A Building, often a brownstone or a townhouse, that has no elevator. Doorman Building: A building that has 24 hours doorman services. Doorman buildings are safer because there is always someone there at the door, admitting people to the building and making sure that people who don't have a reason to be there don't get in. Rental Building: A building that all of its apartments are for rent and is managed by a management company for the landlord. Usually the management company is responsible for the managing of a complex of rental buildings. Laundry/Elevator Building: A building that has elevator and laundry (The laundry facilities are usually in the basement). Types Of Apartments: Studio: A studio is an apartment that has a combined living and sleeping area. Generally, it is one room with a small kitchen in a corner or in a little nook, and the rest of the space is used for living and sleeping. Alcove Studio: An alcove studio is a modified version of a studio apartment. This studio has a "room", which can be used for sleeping, but without a proper door or doorway. 1-bedroom: A three-room apartment (kitchen, living room, bedroom). Convertible 2/Junior 4/Flex 2: A 1-bedroom with a windowed alcove large enough to be converted into a bedroom (4 rooms). 2-bedroom: A four-room apartment (kitchen, living room, 2 bedrooms). Convertible 3/Flex 3: A 2-bedroom apartment with spacious enough for additional third bedroom (dining room, maid's room, etc.). Simplex: An apartment with 1Levels. Duplex: An apartment with 2 Levels. Triplex: An apartment with 3 Levels. Quadroplex: An apartment with 4 Levels. Loft: A loft is a former commercial or industrial building that has been converted into apartments. Generally, these are large open spaces with high ceilings. They are usually found in West Village, SoHo, TriBeCa, Chelsea and lower Manhattan and often do not have the services of a doorman.