Sydney House Prices

If yes how much?

In some areas more than others perhaps, but there will always be areas that are in high demand and there is always someone willing to pay money to live - this is how it happens usually.

Even if it's a declining market, the goods market in Australia is still very strong because it is not enough overall production to meet demand, especially in big cities. Therefore suburbs that are very popular in general maintain their prices.

That is just my opinion well educated.

Yes because of too much debt and high unemployment.