How can someone possible save money on the car repair bill. It's none negotiable. The prices are set in stone. You can save money by sourcing your own parts.
For example, my car needed a timing belt put on it. This is because at it's mileage the timing belt must be replaced. Don't and it will destroy the engine. The price of the timing belt kit, which included the water pump would have been about 200 United States dollars. I sourced my own timing belt kit for 60 United States dollars.
Another example is the downstream oxygen sensor. The price for the sensor when getting it with the repair man was 168 United States Dollars. If I had known he was going to charge this much for it, I would have gotten my own. The cost for the sensor would have been 20 United States dollars. It was too late, he had already fixed the car.
One more example is the front break pads. The parts with the tire repair shop would have charged me 75 American dollars for the same 25 United States dollars break pads. I also saved more when I installed those myself.
You can save hundreds of dollars, if not thousands of dollars by sourcing your own parts. I am not talking about used junk, I am talking about new from the factory parts.
If one does go the route of sourcing their own parts for the repair man, then that one should make certain the part they are sourcing, is an exact fit. That one should make certain it meets the minimum quality standards, just like the broken original.