I think if they still advertise online and you can get the company's to a small claims court if you want the hassle, you might be able to get some money back. But you would need the evidence to back it. Trading Standards don't do much IMO really but might be able to advice you if you have enough evidence to see if it's worth going through with it, and if you can get a mechanic to go with you who has inspected the work and said it's shocking even better. But as I said before they can just close it down and start again with another name. It's almost made that easy for them to do it that way. And will be back trading without you being able to do a thing :(