Co-op board approval is usually much stricter than a condo. They don't have to give you a reason for rejection either. In a co-op you owns shares in a corp., and a right to a dwelling space in the building, but you don't "own" the specific unit you live in. There's more financial risk for the co-op if they get someone who defaults than there is for a condo, so they may put you through the ringer in terms of documentation, etc. The advantage is that co-ops are usually more affordable than condos, if your willing to jump through all the hoops. Make sure you understand the bylaws and monthly fees, whatever you decide. Good luck.