Government, renovation contractors and property agents benefit.
For existing owners at previously lower prices to realise the profits, they must sell. Someone must buy from them.
But they must also buy again for somewhere to live in. That'll be at current market prices far higher and taking away most of their so-called profits.
That's two rounds of buy-and-sell for property agents and two rounds of renovation for contractors. Why else and where else in the world does one find his doorstep and letterbox littered with property agent and renovation contractor flyers on a daily basis.
Government pegs new flat prices on market subsidy basis, not cost subsidy basis. So even when cost of construction comes down with cheaper foreign labour, sale price goes up with the market.