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A new website has opened the books on the nation's house values, revealing the specific losses of our rich and famous - and almost every other Kiwi homeowner.
Where Helen Clark's Mt Eden villa was worth $900,000 at the start of the year, that's now dropped to below $850,000 according to Quotable Value's new My House Value Tracker.
Other famous faces have also lost tens of thousands, if not hundreds of thousands, on the value of their homes, though some have fared better than others.
The new online tool has just been launched and already has homeowners in a mouse-clicking frenzy, with what one analyst calls "morbid fascination".
By typing in a specific address, you can see how that house's valuation has tracked over the past 24 months.
Steve Langridge, QV's general manager of sales and marketing, told the Herald on Sunday the sophisticated new tool had been "created" because of keen interest from homeowners wanting to know the value of their biggest asset - even if they had no plans to sell.
"There has been a lot of talk about what's happening across the country and across different cities. But what does that mean for the owner of a particular property?"
QV used comparable sales in the immediate area to calculate the value of each home.
The results were then plotted on a month-by-month basis, from September 2006-September 2008 and were available for 94 per cent of the country's residential properties.
The Herald on Sunday found My House Value Tracker did not work for many of the country's elite homeowners - such as Jimmy and Gilda Kirkpatrick and their "wedding cake house" on Paritai Drive, John Key's Parnell pad, or former Bridgecorp boss Rod Petricevic's Remuera abode.
But graphs we could access showed a bumpy ride for the likes of Clark, All Blacks captain Richie McCaw (down around $25,000 from a peak of $425,000), World designers Francis Hooper and Denise L'Estrange-Corbet (down from almost $1.5 million to just over $1.3m) and even Tim Shadbolt's Invercargill home.
In general, property owners logging on to the online valuation tool could expect the resulting graph to show growth up until mid or late-2007, then "begin flattening out before declining over the last six months" said Landgridge.
Property expert and publisher of Where to Live in Auckland Stephen Hart said the automated valuation technology was "interesting, rather than utterly reliable.
"They haven't been to see my house ... probably this is more of a novelty, rather than a genuinely useful tool to use every time you make an offer."
He said while the reports were "totally" fascinating, "I don't think we should all go and jump off the Grafton Bridge". Just because QV was aware of other comparable sales in the area, it didn't mean every buyer was, Hart said.
He expected the tool to have negative and positive effects for the country's real estate agents - depending on whether they were trying to get a buyer to up their price or a vendor to become "more realistic".
Peter Thompson, managing director of real estate company Barfoot and Thompson said QV's figures had to be taken with a grain of salt. "It's an estimate only, every house is different."
He said QV's figures were often six-eight weeks behind the actual sale price, and he said Real Estate Institute figures were more realistic. Nevertheless, the new tool was a "good guide".
Free for September, the service encourages those interested to sign up for $10 so they can keep tracking their home's value over the coming 12 months.