The chink in the armor of that theory is that, at least in the West, those apartments are quite well rented out. So as long the rents are paid willingly, there

The chink in the armor of that theory is that, at least in the West, those apartments are quite well rented out. So as long the rents are paid willingly, there is no reason to think money laundering increases rents. I'd even expect the opposite because the investors would have to pay a premium while the tenants' price elasticity doesn't change.