The qualities which make a co-op desireable (mostly owned occupied, somewhat lower transfer fees) must be weighed against the disadvantages to particular owners. If you forsee the need to sublet, a co-op is not an advantage because many co-ops forbid sublets or make them very difficult . In some buildings the requirements to purchase can be extremely strict (no financing above 75% or worse) so when it comes time for you to sell, you have to worry about finding a buyer who will be approved by the Board (condos have no ability to reject your buyer). Also, some co-ops have "flip taxes" which impose a tax on the owner's profit. That's not an advantage either.