This government website has lots of helpful information for home buyers and sellers:
https://www.settled.govt.nz/
Be a confident home buyer or seller with settled.govt.nz. Buying or selling a home is one of the biggest financial decisions you’ll ever make. It can be a complex and sometimes stressful process. Settled.govt.nz will help to inform and guide you through the process from when you're thinking of buying or selling, right through to when you’re moving in or out.