Just this March 2013, I recently went to NZ on a roadtrip for 10 days in South Island NZ.
Attached here is the excel sheet containing our itinerary and costs. (excel sheet here -> New Zealand)
Factors in consideration:
1. This was just for 3 people, but ideally can be up to 4-5 people. (Accommodations might vary a little)
2. Our plan has us arrive in Christchurch, and depart to Queenstown.
3. All of the costs are in AUD
4. Flight not included in the cost estimates.
5. Was during the fall season. (winter you might have a slight change in itinerary, and possibly costs)
6. We searched for promos and discounts in various websites, so prices might vary.
7. We wanted to enjoy on activities, and didn’t really care about food (since there’s really nothing “uniquely” NZ food. So our food was 90% of the time grocery shopping and sandwiches and cup noodles. We only ate out in our last days in Queenstown.
8. We’re not hikers so although NZ has a lot to offer for mountaineers, campers and hikers, our itinerary is just for not so fit people who just want a to relax and sightsee.
9. This assumes you are willing to rent a car and drive around on your own. NZ like AU, is the type of place where it’s best to rent a car and just explore on your own.
Here are the blog entries I have documenting the highlights from the NZ roadtrip:
2. Tranzalpine train ride
3. Franz Josef glacier walk
4. Franz Josef to Lake Tekapo
6. Queenstown and surrounds
If you have any questions, feel free to post in case I might have some ideas on it based on my research.