I tinited the windows in my bus with rolls of miror window tint from home depot. It wasn't all that cheap,,,,,cost me about 100 bucks. I spent about 6 or 8 hours applying the tint. IT looks so much better than the stock windows ! Well worth the effort.
Regular house window tint works on the bus because our windows are flat just like house windows. Automotive windows are generally curved making the tinting process more difficult.
Quis custodiet ipsos custodes (who will watch the watchmen?)