No personal experience, but... The police, prosecutor, etc. are not interested, because no crime has been committed*. An attorney may well cost more than the money you lost, and take years to reach a trial date. As they see it, he didn't keep his promise, but you cannot even prove that without a contract or at least e-mails. NO phone conversation is a contract. Trust nothing you cannot prove.
* This is where language in accusations becomes dangerous. Failure to keep a promise, even a written contract**, is not criminal. "Fraud" requires proof of intent prior to the transaction. Difficult to prove, and legally prosecutable to the accuser and civilly recoverable by the vendor as slander/libel.
** Both parties' signatures on the same document, setting forth the terms including dates, performance, price, penalties, etc. Notarized as an "acknowledgement", not an affidavit and not "under oath".
