Car rentals from North/South Islands
 

Going to New Zealand in January and hoping to spend around a week on the North Island and then head to South Island for a couple of weeks but not totally understanding the whole car rental aspect. If I rent the car at Auckland Intl Airport and then eventually get to Wellington, for the ferry, where do I leave the car and, is it right near the ferry? Also once I get across then I pick up a new rental car? In my readings it sounds like this is the cheapest way to go, although then I need to do the trip in reverse when I head back to Auckland to fly home.

hi Hikin - in fact you have the choice of swapping cars in the way you describe [I'll let others tell you more about that] or hiring a car from Apex which allow you to drive the same car on both islands. The cost of the ferry crossing is included in the price.

https://www.apexrentals.co.nz

We found it very convenient to keep the same car and the car itself was fine. My only cavil is that at Auckland it was quite a long way from the airport to the depot, [there's a shuttle] there was a long queue to pick it up, and there were no loos or maps. They wouldn't even give me a drink of water! So if you are going that route, equip yourselves with maps and water and go to the loo before you leave the airport.

At the other end [Christchurch for us] the depot is on an industrial estate which took a bit of finding, so as it was going to be dark when we dropped the car off, we did a recce the day before. They were a bit friendlier though, but I don't know about the availability of maps, water or loos.

It depends on the car rental agency.

Most will require you to drop off the car at the ferry terminal in Wellie and collect another car in Picton. The transition is seamless as the drop off for the car is right at the ferry terminal.

APEX (and possibly others) will allow you to take the car on the ferry with you and will even cover the cost of the ferry (I believe that's just for the car, not you).

I don't understand why you'd take the ferry both ways. Why not fly back to Auckland from your last point on the South Island? A lot less driving (as you'd have to backtrack to Picton) and probably less expensive. Where do you plan to end your trip on the SI?

I missed that you said you'd be driving back too - IME a bad idea as it would eat up a lot of your time. Driving is not quick in NZ.