Experience is probably the determining factor, $12 an hour would probably be ok for a trainee. You could pay a guy 20% and if they are a competent tinter, they will make $45k + a year as long as you're not doing $99 tint jobs. 30-35% is on the high end of what I've seen. In a cold weather climate, as a tinter, I'd rather see an option of a little lower % for warm months with an hourly back up in case it's slow. So say I make $15 an hour or 20%, whichever is greater. In the summer I'm never making an hourly rate because my % is always higher but come January, it gets a little slow and my $15 an hour ends up being a little more than my %, I get the hourly pay. I've been paid this way before and typically only made hourly 4 or 5 times a year. The rest were %.