Sorry, I can't type Korean at the moment on my comp. Before you do anything, check out this site!!!! www.standbycars.com.au On left under "standby deals", click on "campervans from $1/day" Have a look under "New Zealand"
*** For Campervans; $5/day from Christchurch to Auckland (inc Sth - Nth Isl Crossing Ferry); $2/day from Wellington - Auckland etc.
They offer us this costs as they need to relocate the campervans and cars. For example, during ski season lot of campervans end up down in South Isl and now these campervans needs to be back in Auckland in time for Summer!!! Hence, they need people to drive them back to Auckland etc. ...and if all the conditions suit us then we benefit ^^ One thing though, most of them do have high insurance deposit etc 9just credit card details.. but well worth having a look!!!
Good luck and have a safe and wonderful holiday!
I could give you some tips on Camping but as I cannot type Korean (all of a sudden now), maybe you can let me know if it is needed...