My daughter's car wouldn't start one evening while she was in downtown Dallas. We had the car towed to Concourse and the next morning at Concourse the car started. They kept the car for two days trying to replicate the set of circumstances when the car wouldn't start. I feel they are very thorough and most importantly, fair. They never suggest you do repairs etc. that are not warranted and complete the work for a very fair price. I would highly recommend.