simonjb - And the market has been saying for even more years that it's only a matter of time before the other capital cities narrow the margin.
It might not be a comfortable question for those already holding Sydney real estate. And of course there's no law that says they must consider the question of arbitrage. But given that many believe Sydney in absolute terms - rightly or wrongly - is overvalued, the question may be useful for those who don't want to get out of residential real estate entirely.
The question is also especially relevant, for any young person now wanting to invest in Australian residential property, as to where they should be allocating their dollars. As a rule, a good quality property purchased in most of the other capital cities, should, on average and on the balance of probabilities, enjoy capital gains in the short to medium term comfortably in excess of the equivalent good quality property purchased in Sydney today.
To think otherwise is to think history is bunk - but that needs a very solid argument to be justified.