What's the difference?

A hole in the middle of a living room floor is patently obvious to everyone that visits a home, however what if there's a carpet and piece of furniture over top of it? It will be discovered after a Seller has moved out of the home and the hole is discovered latently! What are the rights and responsibilities of each party:

• Do Buyers have to accept defects?
• Do Sellers have to disclose known defects?