You will not receive your money back automatically, both the buyer and seller have to sign cancelation to return your deposit.
Noone can make you buy. My contracts has a liquidated damages clause initialed by both parties. The amount of the damages is equal to the amout of the deposit. The worse is you lose your deposit. You may have to take the builder to small claims to get that.
Read your contract, call the escrow officer, shout out a question on Trulia. You are doing the right thing by asking lots of questions.
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