We took a whirlwind, ten day, nine night tour of New Zealand by campervan.
Here is our van. It has the boring name of "Delta 08", so we renamed it the Lois McKendrick, of Coffee Share fame. Lois seats four but only sleeps two. The interior space is cramped for sleeping and living, but not terribly so, and the goal was to spend time outside so that wasn't much of a problem. Lois comes with a refrigerator, propane stove, and a portable water tank. She does not have a sink or a toilet.
On day one we flew to Christchurch, picked up Lois, and headed out to a rugged campsite called Waihi Gorge.
The following day we passed through Clinton and Gore on the way to Te Anau, where we saw rare birds. We spent the night at Kiosk Creek.
The fourth day was the highlight of our trip. We went to Millford Fjord, which is beautiful. We took a cruise (NZ$90 each) which was totally worth it.
The next two days we drove hard and reached Wellington. The night before we took the ferry we stayed at a very nice campsite at Kerr Bay in the Nelson Lakes National Park.
In Wellington we went to Zealandia, a nature reserve, where we saw wild Tuatara, Glow worms, Kaka, and a Kiwi! We recommend their night tour at NZ$75 each. We also went to Te Papa, the national museum of New Zealand, which was quite good.
Our final stop was at Rotorua, where we saw the volcanic activity and enjoyed the hot baths.
We would have spent more time on our travels, but we got a good deal to "relocate" Lois from Christchurch to Auckland. So we did a whirlwind trip. We covered 2800 km in ten days. Lois is supposed to rent for NZ$65 a night. We spent on average another NZ$20 per night on campsites and holiday parks. Lois gets only a little better than 10 litres per 100 km, which at current rates (about NZ$2.17 per liter) was NZ$600. Spaceships paid for the ferry fee for the vehicle (NZ$115) but that still left us NZ$50 each to pay as passengers.
We recommend camper-vanning as a good way to see New Zealand. Spaceships were good to us and we recommend them.