I am looking to get mine done soon. There's a local place where all kinds of people from Philly to Dover, to NoVa come to get their tint done. It is the BEST in the area, but it also costs a little bit more than some other places.
To get my 20% all around I think would be $240...but they also have this really cool warranty thing you can buy for $70 where if you ever get a Repair order(In MD you dont get fined, you get an RO to take the tint off within 30days and get it inspected by a State cop at the MVA) they will switch it back to legal tint for free...it also has the standard lifetime no fault warranty and all that.