Sydney's property market is set for a new boom with an undersupply of homes predicted to fuel a spike in house prices.

Clearance rates have been sitting above 70 per cent for seven weeks as a limited number of new properties come onto the market. On Saturday, 734 auctions are scheduled for Sydney in the city's biggest test of the market since Easter.

House price falls have eased some millennials' concerns, but others are afraid they will still be in the family home until they are 30. Credit:James Alcock

The auction weekend comes as data released by property analytics firm CoreLogic shows housing affordability concerns remain severe.

The report also reveals the proportion of Australians living with their parents who believe they will still be at home when they are 30 has jumped from one in five to more than a third over the last two years.