if everyone bashing you is a customer of one mechanic, perhaps that one mechanic is doing something right.
CHARLIE is the one that told me i needed a new condensor for my e46 because I had bottomed out and split it. that sounded very reasonable to me. then he repeatedly asked me to leave a deposit so that he could order the part. that also sounded reasonable. it wasn't until he started to get rude because I was hesistant on putting an 80% deposit on a 900$ part that I decided to get a second opinion. it was that second opinion that saved me quite a bit of money. the actual issue was a sticky valve. with a little lubrcant, some elbow grease and a recharge, i was off enjoying the a/c on a very hot day with money left over to take my mom out for lunch.
and a great lunch it was.
..notice i did not mention where i went to get the second opinion, everyone just knows.
drive it like you stole it... or at least like someone else paid for it!