Legal Question in Real Estate Law in New York

Until the Seller signs, you have no rights because the statute of frauds provides that agreements to create or transfer an interest in real estate must be written and signed. If the Seller did not refund the downpayment and return the contracts to you, speak with an attorney. Do not leave the signed contract in the seller's hands, because if the higher offer falls through, they could try to hold you to the contract, even if you have gone to contract with someone else. If you do not have the check back, consider filing a notice of pendency against the property to protect yourself. It's not cheap but it beats trying to chase a crooked seller after the fact.