Back when I was working for a Mercedes dealer we had a guy that would pin stripe customers new cars. I have no idea how much it cost but it varied by the car size. He would put initials or names on your doors too. Like his on the drivers door and hers on the passengers. Looked tacky as hell on a 80s Mercedes but he was busy and did great work.
I wish I knew someone to do that now, I have an old Triumph sports car I would love to have some roundels and numbers hand painted on, maybe a few logos and make it all look like its been there since the 70s.