The special housing areas were part of a Government agreement with Auckland Council to give consent to 39,000 homes in three years by rapidly rezoning land.
Real Estate Institute head Helen O'Sullivan said she was surprised by some of the proposed sites.
"The brownfields developments are in places you wouldn't expect - like Lake Pupuke Drive in Takapuna."
The median house price in Takapuna - where 70 homes would be built - was around $785,000. In Hingaia, south of Auckland, where one of the largest developments was planned, the median house price was around $420,000.
Under the rules for the housing areas, a tenth of the houses in each new development must be sold for 75 per cent of the Auckland median house price. The median price is about $570,000, meaning some of the homes would have to be available for about $430,000.
Ms O'Sullivan said regardless of the location of some of the development sites, an increase in the amount of properties coming on to the Auckland housing market would help buyers.
"Bringing property to market at any price point is going to help ease the demand pressure we've [seen] in the last 18 months."
She said 37,000 sales were made in Auckland in the last 12 months, so an increase of 9500 homes in the next 12 to 18 months was a big boost.
Ms O'Sullivan said it was important that the new housing areas were a mix of apartments in central areas and houses on the outskirts of Auckland because that created more choice for buyers.
Dr Smith said it would take "a power of work" to get the homes to market, but the supply of new housing was now "building real momentum".
As part of the Government-council agreement, the subdivisions required approval within six months for greenfield developments, and three months for brownfield.
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