She gave the example of Kingsland, which 20 years ago wasn't the trendy suburb it is now - it only became popular after Ponsonby houses became too expensive for some buyers.
"Now Kingsland has sort of moved up in the world, and people are transferring to Sandringham because they can't perhaps stretch their budget to Kingsland any more.
"That gentrification of suburbs is a natural process," Ms O'Sullivan said.
Two of the most in-demand suburbs last month were Glenfield, with 106 properties taking an average of 29 days to sell at an average price of $441,500, and Henderson, with 162 properties taking an average of 34 days to sell at an average price of $380,451.
Barfoot and Thompson's branch manager at Henderson, Michael Henderson, said: "First-home buyers are having a good opportunity to bargain at the moment.
"They're moving quickly because there's obviously good demand, interest rates are low and there is a smaller amount of property on the market."
Those factors meant people were prepared to be a little bit more forgiving than they would have been two years ago when looking for a home.
"So a little bit of paint and paper [needed] is going to be okay when there's only two houses to choose from, but when there's 20 you wait and you look for the one that's perfect."
Alistair Helm, director of realestate.co.nz, said agents selling houses usually did a three-week campaign - long enough in the current market to sell the house.
Ms O'Sullivan said those looking to buy were becoming increasingly frustrated trying to find homes that were affordable, driving them to look outside of their preferred suburb.
Property developer Brady Nixon said the market "pretty much dies" for houses priced at $600,000.
"Anything under 600, you can sell it all day long, but if you go out to Dannemora, for example, you can't even buy a section for 400 grand.
"Plus another $300,000 for a house - you've just pretty much priced yourself out of the market.
"Because of that, the market is pretty dead, and we need land to become a bit more affordable before it can start to take off."
Home easy to sell but harder to replace
Jon Pickford spends his nights looking through house listings online, his weekends at open homes and has put multiple bids on properties.
But even after months of looking, he still has not managed to buy a new home. Mr Pickford has just sold his house in Beach Haven and has to be out by the middle of next month. He's anxious he won't have somewhere to move to. His partner's old house in Browns Bay sold within days of being listed.
However, with the market being so hot in the places they want to buy, the search for a new home has been difficult. "It's action stations at the moment because we don't know where we're going to be in three weeks."
The couple looked to buy in Takapuna or Milford, but the market in those areas had driven house prices above what they wanted to pay.
They broadened their search and are now looking in Glenfield, which was one of the fastest-selling Auckland suburbs last month.
Mr Pickford, deputy principal at Murrays Bay Primary, has made about three pre-auction offers.
"Because of the nature of the market, so many are going to auction so we're needing to put in pre-auction offers," he said. "But then so many of the vendors don't want to take the pre-auction offers because they want their properties to be on the market to attract as many buyers as they can."
