Earlier quoted context omitted.
Their housing market was a ponzi scheme, in that they took money to build developments, but used that money to market new development. Local authorities got their cuts by rezoning areas. Very little likely escaped the country. It's all in country fraud.
Where do you think those local authorities spent their money? They knew the local housing market was no good. Even the things that did get built were Tofu-dreg projects. The bought real estate in the US and Canada.
A similar thing happens in American suburbs where they expand cities with business malls and suburban development to enlarge the tax base but ignore O&M on infrastructure then sell more development to compensate.
But in china, they were selling development with ever building them because it became an investment vehicle.