"The Government will be looking at a longer period of time. By about February next year, we will have a clearer idea of the measures and more reliable information on the scale of overseas buyers and have sufficient number of months, whether it's building consent or sales figures," Dr Smith said.
"I'm cautious in taking a single month of data because monthly figures vary," he said, indirectly indicating he preferred QV information over realestate.co.nz.
"Asking price to me is not as relevant as sales prices. But you need to take all information into account."
Realestate.co.nz said Auckland's asking price fall was reflected elsewhere because the New Zealand asking price fell from $568,215 in August to $539,823 last month , and Canterbury asking prices fell from $476,818 in September to $467,403 last month.
Brendon Skipper, chief executive of realestate.co.nz, said prices had hit a plateau after many months of new record high average asking prices. Those had now levelled off, Mr Skipper said.
QV said values rose most sharply in the city's eastern area, which includes St Johns, Meadowbank, Glen Innes, Point England, Orakei, Kohimarama, Mission Bay, Ellerslie, St Heliers and Greenlane. Values there rose 23 per cent annually and 6.2 per cent in the past three months to hit $1,344,454.
"Home values across the Auckland region continued to show massive value increases over the past year," QV said.
Phil Twyford, Labour's housing spokesman, said the QV data showed attempts to slow the Auckland housing market had failed.
"National's much-touted measure to clamp down on skyrocketing house prices has been totally ineffective. It has failed to deter speculators."
But BNZ chief economist Tony Alexander says there are definite signs that foreign investors have hit "roadblocks" and are showing less of an appetite for New Zealand. David McLean, Westpac New Zealand chief executive, also says the market is changing, citing lower auction clearance rates in particular.
Jan O'Donoghue, QV homevalue operations manager, said the the latest data did not yet reflect changes in the Auckland market.
"Activity appears to have eased a little, which could be due to uncertainty caused by the introduction of new changes aimed at curbing investors in the Auckland market. The new policies seem to have taken the wind out of the sails of the Auckland housing market over recent weeks, however values are still rising, so it may take some time before we know if these moves will have any impact on values," she said.
"Some reports have auction clearance rates at lower than 50 per cent, however most properties are still selling by negotiation afterwards, so this could be due to sellers setting their expectations too high - realistically priced properties are still selling under the hammer. Sales volumes remain more than 30 per cent higher than this time last year, so despite reports of fewer people attending open homes and auctions, homes are still selling well," she said.
More data will soon be out from Barfoot & Thompson, Harcourts and the Real Estate Institute.
Confused?
realestate.co.nz: Auckland asking prices have dropped more than $18,000 in a month
QV: Auckland values increased "massively", hitting a new high of $918,153, up 24.4% annually