Those are two very different careers. One is messy and one is pretty clean. One you might have to work out in the weather while the other you can work inside where it is nice and either warm or cool.

Are you a people person? If so, consider cosmetology. My roommate goes every three weeks, I go every six weeks. He spends about $340 plus 25% tip. I do probably about half that plus 25% tip. It usually takes him a bit under one hour to do both of us and he charges $20 per hair cut. He in essence with both of us, he is make a bit under $50 an hour. You can make your own hours and rent a chair in a local shop.

Being a mechanic - you will probably have to end up working for a larger company because most cars these days are handled by the dealer for warranty reasons.

So decide for yourself how you want to work etc.