Please allow me to elaborate slightly on the heat gun post-this is by far the best way to remove a vinyl sticker.
Use a hair dryer first, this may be all the heat you will need and won't be as likely to light anything. The idea is to liquefy the glue that is holding it in place.
Warm an area about a square foot for a minute or so before you attempt to peel.
Be patient, keep the heat right in front of the peeling sticker. Go slow and you may find the entire sticker and its adhesive comes off cleanly.
As for solvent to use for cleanup, try rubbing alcohol first as this is harmless to just about everything. Then if you need more strength you can go to something more flammable-be careful about open flames and don't use anything indoors.
Kerosene, although unbearable to smell, will break almost any glue without damage to a finish. Don't work without good ventilation!