This is why noone touches my cars.
This.
I saved up to $10K by replacing a "cracked piston" myself rather than use the dealership that diagnosed it. When I tore the motor down myself, lo and behold there wasn't a cracked piston. That makes me 9/10 on getting burned by mechanics. (The one that didn't burn me is a member here that helped me with my wife's Mini, and even showed me a few tricks to make life easier working on that car.)