Hi @Helena815, Welcome to our Community Center!
Are you still looking for some information about Taxes in New Zealand? I wanted to share a general article that gives an idea about how are taxes collected for STRs in the region: Responsible Hosting in New Zealand. (You'll need to scroll down a bit for Taxes section though.)
As our Community Center is a global forum, I would also recommend you reach out to Local Hosts through the Local host clubs. In the above-shared link, I found the link to Christchurch local club below :
I hope it helps you get some proper information from Local Hosts!