Magnetic signs are a good way to go except for the possibility of theft (first hand experience) if left on while away from your vehicle. No..I can't figure why someone wanted the signs advertising MY business. But then again who knows what goes on inside the mind of a thief.
When I had my vinyl lettering done I also had my web address put on as well, I find that more people will link to a web address than will pick up the phone to call
Just my 2 cents worth.
Barger Signs Services Div.