New Zealand has very high quality data. Every single address is in a open database that can be queried or downloaded. It also includes building outlines, roads,

New Zealand has very high quality data. Every single address is in a open database that can be queried or downloaded. It also includes building outlines, roads, land parcel shapes, aerial photos, elevation data and more. OSM for NZ was originally copied from official data, and even before OSM the community used the open data to make high quality map files for GPS devices that were superior to the paid maps. It would be nice for property prices to be included the central government data. It is free and publicity available but from each municipality or many websites that republish the data along with analytics. https://data.linz.govt.nz/ https://data.linz.govt.nz/