There are millions of sources on the use of high-end real estate for foreign money-laundering operations. Like this one: http://nymag.com/news/features/foreigners-hiding-money-new-y...

The question is: why are we allowing foreign speculators in our real estate market, prices where they are, in the first place? Once an average house costs more than 8 times the average income, you have to protect the homeland. Unless you've stopped caring about your own people.