LA, the city where you know your car mechanic before you own a car. I had found a BMW I thought to buy. The seller was an architect too, he changed to motorcycle. I test droved the car and couldn’t tell there’s something wrong. BMWs are reliable. He was asking for a high price but I was confident he knows what he’s doing. But since I don’t know anything about cars I insisted to take it to a mechanic for check before buying. Seller agreed. It took me about a week to find the time. I asked a guy on Hyperion Ave. He was kind enough to check the car for me. So I left it at his garage in the early morning. Later I learned that the car had a problem with the motor. Low compression on two cylinders; cost about $1200 to fix it. The very unfortunate part of it was that the car wouldn’t pass the smog test in its actual condition according to the mechanic. In order to do so the problem with the motor needed to be fixed first. The smog test is crucial. It’s an inspection that certifies the car meets exhaust regulations which are very strict in California. You need to pass it when the owner is changing. I was lucky I didn’t buy a problem, thanks to the mechanic. I felt sorry for the owner of the car. Completely unaware of this problem he doesn’t know what to do now. Although the car passed the smog test 6 months ago when he bought it, and the low compression is something that doesn’t occur from one day to the other, as I learned, he risks the car failed the test and would be disqualified for registration until the motor problem is fixed. Instead of selling, he needs to buy first, as it looks like. And I know a mechanic, before I have a car. I will go there again next time I consider buying one. Assistance. Another potential seller told me the day after I saw the car that he learned the car needs a minor repair in order to pass the smog test and being sold. I haven’t heard from him anymore since then.