The region's lifestyle was a big drawcard, he said.
"We've got good schools, we're five minutes to the airport and 20 minutes between the cities. There are no drive times."
With a median Hawke's Bay sales price of just $285,000 last month, "you get a lot for your money", Mr Tremain said.
"For a million dollars here you're on the beach with a substantial home in the best locations, or you're in Havelock North in a beautiful north-facing spot with fantastic views."
However, incomes were lower in provincial New Zealand and it would be difficult for buyers who sold-up in Auckland to re-enter that market, Mr Tremain warned.
Aucklanders have newly acquired equity thanks to soaring house prices which hit a median of $720,000 in the city last month - a 13 per cent jump in the past year alone.
The annual capital gain on a standard Auckland home was on par with the salary of an entry-level doctor or head of department teacher with responsibility for 10 staff.
The rampant property market has sparked warnings from the Reserve Bank and calls for action from the country's human rights watchdog.
Luxury Real Estate agent Charlie Brendon-Cook said the number of Aucklanders buying top-end Bay of Islands properties had surged in the past six months to about 50 per cent of total sales.
"Some are holiday homes to live in later, but they're definitely on the back of new-found wealth in Auckland. That's a very noticeable trend."
Some Auckland buyers had purchased homes for $300,000-$400,000 which were now worth $1.3 million.
"They can sell that and put 600 or 700 [thousand dollars] into a property up here and live off the difference."
