Can tint be put on top of tint or does it have to be removed? What kind of issues can I expect if I layer it? thanks.

expect it to be darker for sure... I had a few trucks years ago that I tinted with 2 layers of "secret zone" 2% limo tint if I remember right....

It was hard to see out of even in the day light. I would never want something that dark again.

Well I currently have 15% tint and I want to throw in there an additional %20 tint. Im thinking it should end up right at, or slightly below limo tint.

what's the point? just take it off and tint it with limo

i wouldnt recomend it... just redo it 10% you cant see in at all