A Belfast estate agent has said that phases of two new-build developments have been selling "rapidly" - with sales of over £3.5m in the last eight weeks at one of them.
Tiffany Brien of Simon Brien estate agents said that it is selling 30 to 40 houses a week.
And she said that many of the houses at the Rivenwood housing development in Newtownards, and at Belfast city centre apartment development FX, had been booked before they were launched.
Rivenwood is being built by Fraser Houses and will eventually include 1,000 houses.
And Village Homes, a related company to the Fraser group, is also behind the FX development of apartments in Montgomery Street.
Ms Brien said: "Rivenwood is a magnificent suburban village development in Newtownards and has been popular for first time buyers, young people starting out on the property ladder and those who are downsizing.
"Whereas in Belfast city centre, the FX is more for the young professional or someone who wants a bolthole in the city or a place to stay when they are here for business."
More than 500 people turned up for the opening of Rivenwood's show village in September and sales have exceeded £3.5m in the last eight weeks.
She said there had also been strong demand for the FX development, with 28 of the 36 apartments booked by the release date.
The latest government residential property price index for July to September said the average house price in Northern Ireland was £139,951, up 4% year on year.
A separate report by Zoopla puts Belfast's average price at £137,600, also up 4%.
Looking ahead, Ms Brien said: "Overall it is very positive and looking forward to 2020, the main issue is demand outstripping supply and we would like to see more private homes coming to the market as well as new developments obtaining planning consent to enable more new homes to be offered to the market.
"While market confidence and house prices have grown steadily since the market 'bottomed out' in 2013, the fact that our average house price is one of the most affordable in the UK and the rate of growth has been at a steady sustainable level, augurs well for the 2020 market and beyond."