I was cleaning my windows today and it seems the ammonia concentrate was too high in the window cleaner and it messed up the tints on 3 of my windows.I went to the shop and basically a lot the guys in the nyc wants to charge me $500 to remove the existing tint and redo all the windows and rear glass.Is this the going cost or is it too high ?I can remove the tint myself but wont mess with the rear glass for fear of damaging the defogger strips.That should reduce the cost.What do you guys think?