1. Most people who are buying real estate on the coasts don't care about the exchange rate. They don't even care about the value of the assets they are buying. They are doing it because they are buying security, a backup plan, a diversified investment that can't be clawed back by their government, or exposed to the fortunes and misfortunes of China's economy.

2. Most of these buyers are doing it while illegally avoiding capital controls - not with the blessing of the government. It's why Canada is such a popular destination for this money - it has no reporting requirements. The whole point behind China's exchange rate policy, is that it allows US dollars to enter the economy, but due to capital controls, not leave it (Without being subject to the 'tax' of unfavourable exchange rates.) Chinese nationals buying property in North America are not working with the policy. They were working against it

And yes, there's plenty of folks who do have a direct line to the politburo (Or, more likely, black market channels for exchanging money), and can turn their yuan into USD, without trouble, and then get that USD out of China. I don't think they are responsible for the majority of capital flight out of China.