Camper vans and rental cars probably account for at least 50% of vehicles on South Island roads, and there are even stretches of highway posted for free camping for fully contained RVs.
There are many styles available, but the lime green Jucy cars and campers were the ones that caught my imagination. Every Jucy vehicle has a fun saying on the side.
One of their rental cars said, "Always take the scenic route - especially if you are lost."