University and polytechnics make finding a flat easier as there are often a significant number of flats that are already rented by students. Each institution has an accommodation office that’s a good place to start to get information and contacts. Dunedin in particular has a powerful flatting culture and there is a big concentration of these flats close to the university.
Other ways to track down a flat include checking out Trade Me, looking in your local newspaper and asking real estate agents what they have to rent. Another good idea is to advertise on student noticeboards, or to even ask older students who may be leaving their flat at the end of the year.
If you’re looking on your own for a room to rent, start by checking notice boards at the university or polytechnic, or put your own notice up. Trade Me again can help, and so can social media. You never know what a message on Facebook might turn up for you.
More good info:
These eBooks have plenty of useful information about flatting, even if you're not a student
Student’s Guide to Living in Auckland
Massey First Time Flatters Guide
UC Guide to Flatting
Otago University Flats Handbook
Victoria University Flatting Guide
Flatmates wanted and rental accommodation websites:
Trade Me - Flatmates wanted
Try searching for a 'Flatmates Wanted' public Facebook group for your area.