The other thing you need to worry about when adding window tint or some other mods is your insurance. Depending on the carrier, thay can deny your claim if you have an "illegally modified vehicle."

Most won't but it's a big claim they will try every trick in the book to find a way to deny it. On the other hand, a ticket for tint can absolutely raise your rates. Many insurance companies have this clearly listen in thier policies. This is directly from Progressive's website:
"Do window tint tickets affect car insurance?
A window tint ticket can affect your car insurance rate, just like any other violation on your record. Plus, if your tinted windows are darker than the legal limit and you get into a covered car accident, your insurance company may not pay for all damages to the illegally tinted windows. Depending on your insurer, there may also be other potential effects to your car insurance policy."