Oh my, but does Wellington have one very useful little house-shopping tool.
Wellington Region Combined Earthquake Hazard on Koordinates
Put in any address, and it will tell you the combined earthquake hazard risk.
I expect it would be easy for TradeMe Property to scrape this data via the API; it's Creative Commons 3.0.
While I'd appreciate it if TradeMe got this running while I'm house-hunting, their implementing it might lead to a price premium on quake-safe housing. I'd consequently prefer that they hold off until after I've purchased, despite the minor inconvenience of having to manually search each address.