South Australia recorded a decrease in sales volume over the third quarter of the year but its unit market remained “on fire”, according to the latest market update by the Real Estate Institute of South Australia (REISA).

Over the quarter, only 3,605 houses were settled across Adelaide's metropolitan area. Sales across the entire state were also down from the previous quarter. REISA president Brett Roenfeldt said the moderation in sales activity is a normal occurrence during the third quarter of the year.

"The third quarter is always traditionally a slow period for sales and these results are comparable to the same quarter in previous years.  However, the figures also show that realistically and transparently priced properties continue to sell well," he said.

SA median prices update

Despite the low sales volume, the state's median house price remained steady, growing 1.19% from the same quarter last year.

"The great news is that the median price continues to remain high, and this is surely a sign of the underlying confidence and resilience of our property market," Roenfeldt said.

South Australia's unit market, in particular, showed substantial growth, hitting a 7.56% gain in median price to reach a new record level of $370,000.

Also read: The best-performing suburbs in Australia

Top-performing suburbs

REISA's market update listed certain suburbs that recorded robust price gains over the past year, including Evanston, Taperoo, Gulfview Heights, Munno Para, Greenwith, and Munno Para West.

In terms of sales activity over the quarter, the top-performing suburbs were Morphett Vale, Hallett Cove, and Aldinga Beach.

"Affordability, location and a sound investment opportunity will always be the key drivers of purchaser decision making and suburbs that show these qualities will always perform consistently and well.  This is why the same suburbs appear in the top sales list every quarter," Roenfeldt said.

Opposing land tax reform

The growth in South Australia's median price is an optimistic sign for the housing market. However, Roenfeldt said the proposed reforms to land tax could potentially harm the market's positive outlook.

"We must oppose measures that are doing nothing except to create uncertainty, undermine confidence and force our traditional mum and dad investors into spending huge sums of money in restructuring or giving up their property portfolios altogether," he said.

Also read: SA to push with land tax changes

The land tax reform aims to prevent property owners from creating complex trust and ownership structures to slash their land duties. Negotiations between the government and stakeholders are currently underway, but the Labor Party remained against the proposal.

"This bill increases land tax on South Australian small business and property owners, not decreases it. That will have a substantial implication on small businesses — whether you're a tradie, whether you're a retailer, whether or not you're a panel beater, this is going to have an impact,” Opposition Leader Peter Malinauskas told ABC News.