To follow up on my own post, I found many car dealers who would bring a car to
the airport for me There does not seem to be much risk in buying a high grade japanese import (aa inspected etc).
In the end amongst all the negotiations one of the prospective sellers offered me a long term deal at $20 (NZ) per day.
Eliminates all the questions of registration fees, insurance, disposal. So that is what I will do.