"[Election year] always puts hesitation in the marketplace."
Winter was never a good time for listings, but the high expectations of local buyers were also contributing to sluggish activity, Mr Keane said.
"They're saying 'Look, I'm not going to get enough money for the house, so I'm going to stay with it'."
People did not realise now was actually the best time to sell, he said. "There's less stock, there's less choice for buyers, so they have a better chance of selling if the price is right."
Several high-end sales in Napier during June had dragged the median house price up.
The number of houses sold nationally in June fell 6.3 per cent compared with the same time last year, with the number of sales below $400,000 falling 17.3 per cent - an expected outcome of the Reserve Bank's home loan restrictions.
June's national median price rose $33,250 from the previous June to $427,250, but dipped by $2750 from May.
Reinz chief executive Helen O'Sullivan said it was now taking five days longer to sell a property than it did 12 months ago.
"Volumes continued to trend down in June, as they have done for the past several months. We are starting to see a number of regions record annual falls in the number of sales at around 20 per cent, with only modest increases in those regions where sales numbers are rising."
Central Otago Lakes recorded the largest increase in median price compared with June last year with a 12.9 per cent jump, followed by Canterbury/Westland with 12.3 per cent and Auckland and Taranaki with 8.1 per cent.
House price inflation in Auckland, Canterbury and Westland continued to dwarf the rest of the country.
"Over the past seven years the national median price has increased by 23 per cent, however only Auckland and Canterbury/Westland have seen prices rise by more than the national median at 35 per cent and 34 per cent respectively."
However, regional New Zealand had experienced little change in the median price in the past seven years.
"Eight regions, representing over 43 per cent of the New Zealand real estate market, saw their median price increase by less than the change in the Consumer Price Index over the same period," Ms O'Sullivan said.
The Reserve Bank last month lifted official interest rates from 3 per cent to 3.25 per cent, forecasting a rate of 5 per cent by 2016.