Not satisfied with Garage work

[tarotcards]

Hi everyone..... I wonder if there is anyone who can help our Son with the trouble he is having after his car has been returned from the Garage. It originally was to have the Engine Cylinder Head skimmed as it was noisy. He telephoned the owner beforehand and received a verbal estimate of the work to be done of around 250.00. This was accepted and the car went there. During this time the owner was admitted to the Hospital for an op that he was waiting for and the work was carried out by another employee. He telephoned several times to see how the car was getting on and it was in the garage for a few weeks more than he had thought. The car was collected but it did not run properly . but it was revealed that there were some bolts missing from the block, and it was leaking oil. On top of this our Son had a bill of over 1000.00, and he was informed that the employee that had worked on it is not qualified and has no certs, as the owner of the Garage is well aware , as far as we know by word of mouth. He has informed the owner of the findings and dissatisfaction of the works and all he said was that he would knock a 100 off the bill and for him to take the car back. The following day the engine seized up and it is now stored in another garage awaiting for an engine that is to cost him over 400.00 together with the fitting of this of 250.00. The other Garage owner has informed him that he will take him to the small courts if he does not pay and that the employee( who has a reputation) was supervised by another whilst he was working on the car. We do not understand why, if this is so the car came from there with bolts missing and loosing oil. Our Son took the car to be tested and he was informed that it was very doubtful if the cambelt was replaced and new seals applied at the time as this would of had been essential if any work has been carried out on the engine. Can anyone tell us the best way for him to go about this, as if nothing can be done the whole amount that he will have to pay out is amounting to £1,650, instead of the original estimate of 250, and then there is VAT on top of this. Many Thanks