Since most home builder selling new houses that have not been built, and they want you to put down at least 10,000 dollar for deposit. Your banks or financial institution may pre-approve your mortgage, but this does not mean they will 100% lend your the money at the time of closing. If your financial situation change such as job loss, banks will not give you the mortgage at closing; and since you sign a contract to purchase the house, the home builder will keep your deposit. Therefore, the most improtant term is to have the option to get your deposit back if you can not get a mortage at closing day.