There is no need for you to go the Court the agreement already stood cancelled by efflux of time and by giving notices to him. If you had given him notice stating the agreement is cancelled and he is free to suggest mode of refund of advance that will close the matter. If he wants to enforce the agreement let him go the Court. He has first deposit the full sale in the court and pay court fee and lawyer's fee then only his suit will be registered and even if a suit is filed the time to execute the sale deed has lost and it will dismissed. Dispute cannot be taken to police as the same is civil.