Australia's is toothless though, in that enforcement is minimal and so are the penalties. NZ's may be equally crap or it may be quite effective, but I haven't seen details on the above and so it's hard to compare the policies at this point. A policy like Thailand's, where those found to be buying against the rules have their property taken off them without compensation, would be ideal.

The next step would be to require that those that do not meet the rules sell up, which should put a bit of supply into the market and achieve some meaningful price movement.

Another good step would be to finally bring in a decent capital gains tax, ideally charged annually on paper profits at whatever your marginal tax rate is, and with no family home exemptions. Ironically taxing the family home would, in this case, actually make them more affordable by exerting further pressure to move speculators out of the market.