As the others have said, report to rated people
Also take as many photos and keep any messages/mails you have had with this individual
Have you paid this individual if so depending on how much you paid it may be worthwhile trying to recover your money in a small claims court
Its a fairly cheap and good way of recovering your money
That sounds terrible. I'm a tradesman myself so I would recommend you get in touch with Rated People directly and let them know this situation first hand and they will deal with the tradesman personally. He'd probably be struck off. I hope this helps you.