The answers you've already gotten are good except for one thing. A condo is not necessarily or even usually single story and a townhouse is not necessarily multi-story though many are. It's a townhouse if you own the land under it but the house is connected/attached to one or more adjacent houses. It's a condo if you do not own the land, only the space inside the walls. WIth the condo you usually also own a percentage of the common areas but it's not a defined space, it's a percentage ownership of the entire common area.
A townhouse HOA or PUD may include exterior maintenance but you own the exterior. A condo association almost has to include exterior maintenance because you don't own it, at least not entirely. The condo owners share ownership. A condo can be a unit in a large multi-story building.
Some people will refer to a townhouse style meaning any 2 or more story home with no other unit above or below yours. But a home of that style can be sold as a townhouse or a condo. - Sat Apr 26 2008, 22:58
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