Sir, this is the time to consult, 1, your real estate agent, and 2, an attorney.  A default on closing means that the buyer has put you out a great deal and you DO have the right to recover.  Any more than that is best kept under the umbrella of client privilege.  Be sure to read all the fine print.  If you sue for Treble Damages and get a judgment, and the defaulting party has nothing to lien, you could be up against a legal nightmare.  That is where "discovery" comes in.  Either way, this is time to retain "privileged counsel" regardless of expertise.