Boston Apartments
An apartment (or sometimes flat in Britain and most other Commonwealth countries) is a self-contained housing unit that occupies only part of a building. Apartments may be owned (by an owner-occupier) or rented (by tenants).
Some apartment-dwellers own their apartments, either as co-ops, in which the residents own shares of a corporation that owns the building or development; or in condominiums, whose residents own their apartments and share ownership of the public spaces. Most apartments are in buildings designed for the purpose, but large older houses are sometimes divided into apartments. The word apartment connotes a residential unit or section in a building. Apartment building owners, lessors, or managers often use the more general word units to refer to apartments. Units can be used to refer to rental business suites as well as residential apartments. When there is no tenant occupying an apartment, the lessor is said to have a vacancy. For apartment lessors, each vacancy represents a loss of income from rent-paying tenants for the time the apartment is vacant (i.e., unoccupied). Lessors' objectives are often to minimize the vacancy rate for their units. The owner of the apartment typically when transferring possession to the occupant(s) gives him/her the key to the apartment entrance door(s) and any other keys needed to live there, such as a common key to the building or any other common areas, and an individual unit mailbox key. When the occupant(s) move out, these keys are typically be returned to the owner.

Apartments can be classified into several types. Studio, efficiency, bedsit and bachelor style apartments all tend to be the smallest apartments with the cheapest rents in a given area. These kinds of apartment usually consist mainly of a large room which is the living, dining, and bedroom combined. There are usually kitchen facilities as part of this central room, but the bathroom is its own smaller separate room. Moving up from the efficiencies are one-bedroom apartments where one bedroom is a separate room from the rest of the apartment. Then there are two-bedroom, three-bedroom, etc. apartments. Small apartments often have only one entrance/exit. Large apartments often have two entrances/exits, perhaps a door in the front and another in the back. Depending on the building design, the entrance/exit doors may be directly to the outside or to a common area inside, such as a hallway. Depending on location, apartments may be available for rent furnished with furniture or unfurnished into which a tenant usually moves in with his/her own furniture. Permanent carpeting is often included in an apartment.