I too am in the same boat. 25, recently engaged. I worked thru high school at a local shop working on foreign japanese cars. Then I joined the GM program thru a pontiac gmc dealer. Did that for almost 2 years. Then I got a seasonal construction job for the City. It paid good during the 9 months I work. Then in the winter season I drove a snowplow for the state. It made ends meet but I realized it was just not practical.
So I have applied with the local county sheriff. I went thru all the processes, now its a waiting game. The drawbacks are the hours, having to work nights and weekend makes for less boating time.
I too have kicked the idea around of opening a shop on my own. I would love to open a full service detail/custom shop. I thought about buying a piece of property just outside of town, and putting up two metal buildings. One for a Full service detail center for cars and boats. The other a shop for stereo installs, alarms, truck accessories, spray in bedliners, etc.
My advice, take the chance now, if we do and fail, so be it. If we dont, everyday we go to work, we will regret it. Good Luck, MT