You guys are all asking the wrong questions and making assumptions.
Show of hands, how many of you out there have successfully BACKED out of a contract for a new construction home and the builder refunded all deposit(s) WITHOUT you making threats of legal action?
I haven't heard of anyone myself but I'm sure there might be a few, however, I'm sure they have extenuating circumstances beyond their control (spousal death/dismemberment).
Clearly, the builder wouldn't want people to just back out due to cold feet, otherwise everyone would be doing it. All them _____ people would be backing out left and right or selling their spots in line, or some people would be making a deposit on 4 homes and then backing out on 3 just to buy the best 1, etc.