I’m reasonably mechanically inclined and I thought I had major problems with my BMW. Check engine light, running rough. Pulled the codes and came up with 4 different ones, did some research on the internet and best case scenario it was going to be a 5 hour labor bill plus parts. They called and told me and it was a simple fix. . I did the repairs myself, it cost me like a 60 dollar diagnostic fee. I’m sure I got lucky, but they didn’t hose me. Next mechanical issue I have that I feel is beyond me, Charlie’s is getting the first shot at it.