When you ask about a "townhouse" are you thinking of the multi-level variety of condominiium? Sometimes people think a condo is a single floor unit, like in a hi-rise, and a townhouse is a multi-floor unit -- usually with its own separaate entrance.
Actually, both are considered "condominums" for the purpose of adviertising, in that the ownership form is "condominium" as opposed to "fee simple" for a single family home,
In Westfield, Trinity Place and Prospect, for example are both single level units, while Orchard and Fourth are both multi-level.
Hope this helps ... if you need more, feel free to contact me at http://www.westfield-area-homes.com
... or email me at email@example.com.
Teri Malone, Weichert Realtors