4826, I don’t know any details about Aussie RE, but I have kept vaguely aware of its movements for the last 20-30 years.
My definite impression is that Australia went into a bubble every bit as inflated as So Cal, and maybe even more in some places.
If I were you, I’d look for a good long-term house price series for Australia, like our own Case-Shiller. After looking at it, and comparing to something like per-capita GDP, you’ll have a better idea where current Australian prices are in the up-and-down cycle, relative to the last 20-40 years.