Condos increase your buying power. Compare the price of a two-bedroom condo to a two-bedroom detached single-family dwelling in the same neighborhood. On the basis of livable square footage, condos generally sell for at least 20 to 30 percent less than comparable detached homes. Owning your very own roof, foundation, and plot of land is much more expensive than sharing these costs with a bunch of other owners. For some would-be buyers, the choice is either buying a condo that meets their living-space needs or continuing to rent.

• Attached residences generally cost less to maintain than detached homes. Although replacing the high rise's roof, for example, costs more in absolute terms than replacing the roof of a detached single-family home, the cost per owner should be less.

• Attached residences have amenities that you couldn't otherwise afford. Most homeowners can't afford expensive swimming pools or tennis courts.

• Attached residences are ideal homes for some empty nesters. Perhaps a building with no maintenance hassles and a doorman who'll forward your mail while you're off on one of your frequent vacations might be right for you.