I worked there for 5 years..average scaffolder get $22 - $25 per hour grossing $1200 per week for 5 days. Cost of living is high, food, bills, petrol. If you have a young family financially you go backwards. You need two incomes to get by.
I was managing a company and on a good salary in NZ terms, but still found it hard.
Saying that though great place to bring up kids, nice and safe. no crime, you can leave your house unlocked and car running when you pop into a shop. Sceney is fantastic, thats why so many films are made there. South island is cold 6 -7 months of the year, but great for skiing. My kids went to school and they ski for a whole day during ski season.