Jimp - it's a small world. LOL
Tint isn't as forgiving as decals. All it takes is a single piece if lint to ruin a window. Squeegies are soft rubber, bondo spreaders will scratch it badly.
To trim, to apply the tint backwards on the outside of the window, squeegie it down, and trim. Then, remove the protective film and apply to the inside.
Yes, it is relatively easy to damage. Not near as durable as a decal with the protective later on top. With tint, you are squeegie directly on the tint surface.
Todays curved glass usually requires a heat gun to heat shrink the tint and force it to conform to the curve. If you don't, it's like trying to wrap a bowling ball.
My point is that if you diy, and have never seen or helped someone do it, you will most likely be disappointed.
And it is a whole lot harder to remove than apply. The glue is a serious pita to get off.
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