As far as a wrap, I don't have that kind of money.
I painted it by hand instead.
You can see it peeling off of the glass, but I just patch it up every now and then ( about once every 4-6 months.
And as far as the windows, all of them have advertising - except the ones I need to have clear for legal reasons.
Magnets ? I was just outside earlier and a gust of wind blew a branch out of a tree near me. I think I will be using bolts, or self tapping screws.