There is no need to prep for it. They give you all the booklets for the Public Acts and part 8. All the questions they ask are in there, and they give you more than enough time to find them. You can find study guides for it. Cossin sells one for like $75.00. A bunch of us took it at the same time, most of the guys bought the cossin guide. I didn't and got a 95%( And i'm no where near the sharpest tool in the shed) they got the same or 100%. The worst part is the Public Acts are written very dry, so it is hard to not fall asleep. Good luck.
The license is 300.00 every 3 years, I hope you have some work lined up. With Michigan's economy the way it is, every one is cutting each other's throats for work.
I got mine with the hope's of supplementing my job income on weekends and after work. After I paid for the license, liability,and tools. I haven't made much but I hope thing will pickup soon. Thank God for not quitting my job.