So let me get this straight..... You called about the building; negotiated a price; signed a contract and then put down a $3000 deposit. You did all that and didnt think about changing your mind. Then you changed your mind and decided not to go through with the contract.....
And now you want your deposit back?!?!
Seems to me like this is your fault. 100% your fault. You are lucky they are a good enough company to give you a $3000 credit on a purchase in the future. How are they supposed to stay in business if they allow every person who changes there mind, out of the blue, and not honor the contract .... which by the way, they signed.
I'm just really surprised that you expect your money back even though it was your choice to to not uphold the agreement. It was 100% your fault.