right yes but when you go for extension you will need an MT30 form, a passport size photo and passport then you fill in another form while you are there and pay 1900B. Also copy of your passport, some centres do it for you.
You and your friend can do an MT30 on line and just put his address, when you get it back just print and keep it for when you go to apply for the 30day extension.If you stay at a resort you can ask for an MT30 but quite often they won’t supply them. You could get your friend to send you a letter inviting you to stay with the address clearly in the letter, you can show this if asked by immigration when arriving.
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.