Thank you that was really informative. I paid <$50 for my IP address in 2015. My ISP has been around since 1990 so I suppose they may have been one of the lucky companies. Not sure if they do RPKI, first I'm learning of it. Maybe they're cross subsidizing from other areas of the business. Their monthly fibre fee isn't the most competitive but the service is reliable and haven't had anything to complain about.
They are a little behind in speeds though. They only offer 900mbps asymmetrical max, while you can get 2, 4 and 8gbit in my area from other providers. I don't need that kind of speed so I'm happy for now.
Not sure. But I often see people recommending buying a second hand dell optiplex or similar for home servers, and it doesn't seem to make economical sense here. But don't have any objective data to offer, just an impression.
Interesting point about trademe listing vs actual sale prices.