You cannot use a Private Box address as proof of address. We are a postal address only; you cannot claim that we are a residential address for any reason.
You can produce proof of address if you have an IRD number. You can apply for an IRD number via https://www.ird.govt.nz/managing-my-tax/ird-numbers/ird-numbers-for-individuals/
Once you have a myIR login you can obtain proof of your address via
If you need to set-up a bank account, see our article about that.