The foreign millionaires are a small part of the market.  Most of it has been locals who believed 1) if they did not buy now the house would cost more tomorrow, 2) it did not matter what they paid because the house would be worth a lot more next year, and 3) cheap money would last forever.  Such conditions always lead to market contagion and a bubble.  If interest rates keep rising, that should puncture this bubble.  It always has in the past.
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