Seller backing out in NY

[Stefan M.]

I've read similar threads here before but couldn't find the answer I was looking for. Basically we are in the process of buying a coop unit in NYC. Seller agreed on the final price a few days back and sent the contract to our attorney. We made some changes which were accepted by the seller's attorney and signed the contract yesterday morning. It was delivered to seller's attorney right after. 10% deposit check as well. Also paid fees to our lawyer. Low and behold at 11pm we get a call from the seller's broker that they have another offer which they would like to entertain so they won't be accepting our contract. We spent money already and a significant amount of time. We also passed on another unit because of seller's acceptance of our bid for this one. Is there anything that you can suggest doing at this point? Bid higher? Sue for specific performance? Or just drop out and accept a loss? Thanks.