Legal Recourse against Tuner

[malazn mafia]

Hi all, just wondering what sort of protection there is for the consumer against shonky or incompetent tuners? Basically I have given my car to the same tuner for an LPG conversion, turbo upgrade and engine tune. He has had the car in the workshop 3 times, and I've spent in excess of 10k with him. The car has gotten worse and worse each time. It made fantastic power (360rwkw), but had serious issues during idle or warm starts, and switching between petrol and gas. Between the 2nd time he had it and the 3rd time, the car suffered a head gasket failure. After the repair ($3500) and he had given it back to me after many weeks off the road, the car ran worse than ever, and the turbo seized within 30km of driving it. He replaced it free of charge and assured me the car was now spot on. Sadly the car was not, and it was barely driveable, and as a result, in an unfortunate incident, I was involved in an accident after the car stalled at the worst time possible. What legal recourse does the consumer have ? After this incident, I was so upset that I refused to drive the car or go back to the tuner for fear I would erupt in fits of rage. I don't expect the tuner to bear the costs of the repairs from the accident or anything, but I think it's rather ridiculous that I have spent more than 10k and now can't even drive the car. Anyone had a similar experience or know who I could talk to ?