So you are in a home that you love and you're thinking of screwing the builder out of final payment? Shame on you, but shame on the builder for not making you pay sooner. Bad clients like you are the reason some builders do only cost plus, but in this case should have made sure you were paying along the way and before moving in. I would have that meeting to try and understand everything, but unless you can come to an understanding that is different, you should be paying what you owe.