Caveat emptor is an old Latin expression that basically means that buyers should be careful when buying. In this article you can read about what you should be aware of when considering buying a new home.
Interest is a strange quantity. When buying a home, most of us have to borrow some of the purchase price - and then we have to decide on the terms on which we want to borrow. Here you can read a bit more about the basic considerations you need to make when borrowing for your new home.