I'm going to do my own mechanic work
Why don't you bring it to a mechanic?
I don't trust strangers to work on my car.
It is good to do work that you know how to do. There are trained professionals that might be able to do a better job than you. They might also have better tools that you need.
Nah. I've been doing this way longer than the school's mechanic classes.
It is good to learn to work on your car to save money. But you should know if something goes wrong you wont have insurance to cover your losses.