I have had some stickers made up for my car.
Told the sign company it was for the car and was not going to be put on forever, so must be able to take them off with no damage to the paint.
Been doing this for the last 3 years and so far no problem. It will depend on the paintwork your putting them on.
When you take them off choose a hot day and they should come off dead easy or use a hairdryer to soften the glue under.
If any glue left on the paintwork try a bit of WD40, that worked when I took the stickers off my van, and they had been on there for years.
Oh yea, before you put them on, make sure the paintwork is clean and dry.
Failing that, Paddy will know more than me, I think he has a bit of experiance with stickers

So are we going to see a Gulf colours horse box? Cool