"Also, first homebuyers who need time to arrange their finance may miss out," he said.
According to QV's residential price movement index in the year to July in Whangarei, house values increased by 5 per cent to $351,837; in the Far North, values increased 5.4 per cent to $312,903; and in Kaipara, 8.5 per cent to $366,908.
Mr Beazley said Northland was benefiting from the ever-rising price of properties in Auckland.
Properties selling between $265,000 and $285,000 12 months ago in Whangarei were more likely to sell in the early $300,000s. Thirty-five to 40 per cent of buyers are out-of-towners, predominantly from Auckland, he said.
Three-bedroom homes selling for around $300,000 were the most popular.
"I think this time is shortening as the market heats up and demand grows," he said.
Winter is traditionally a slow time for property sales in Northland, but with some homes selling after just a few days on the market, spring is expected to be especially good for sales.
Barfoot and Thompson Whangarei branch manager Martin Dear said the market had become very competitive.
"We're getting heaps of pre-auction offers and back-up offers that are more than the initial offer coming in," he said.
"Buyers are coming in, not only from Auckland, but also locals, paying over and above asking prices."
Buyers had to act fast to secure properties, he said.
"As it becomes a vendors' market, there's more buyers to a property. You could take your time in the past, but now there is a hurry. We're way up on our turnover from this time last year, as I think a lot of offices are. Things are getting busier and busier."
Fortunately, some new stock was coming in to the market, he said.
"People are starting to realise the prices are there so they're putting their houses on the market. There's also a lot of rental properties vendors tried to sell off a few years coming back to the market."
QV national spokesman Andrea Rush said there was a definite upward swing in market activity in parts of the North Island including Whangarei.
"Net migration remains at record highs and there are now incentives for new migrants to move to areas outside of Auckland, so this, coupled with record low interest rates, is likely to see continued upward pressure on home values as we move towards spring."