From what I have read, if you are doing it yourself, the first one has to be done in person, then next can be done online, but for 300, I would let agents do it
I am kiwi, but been living in Aus for 18 years. I just moved to Thailand last month. I just came on the 60 day visa free, then paid agent to do visa for me, if you get retirement visa from NZ you will have to buy insurance, as much as I believe you will need it, it can be purchased cheaper in Thailand.
You will both have to go through the same process.