I just made a visitor visa through NZ immigration for a Thai visitor and was not asked for a return air fare. The last time I did it they were given 3 months this time 6 months.
Don’t have a link but that is the rules, just as the hotel for a copy of the TM30 so you can take to immigration.went to immigration once didn’t even know about TM30 but was the first time I needed to get an extension, when we were asked for an MT30 we said didn’t know about, asked were we were staying and they went straight around to the landlord and he was find.