You or your REALTOR can notify the sales associate that you will not be closing on the home and want out of the contract. This will put you in breach of contract and Southgate will determine what steps if any they will pursue. You will typically lose all your earnest money (see below) and any funds you spent on upgrades. I have never had a client get sued for specific performance or 'forced to close' on any new construction home. The builders typically will just sell the home to someone else and keep your money.