[charlesdm]

Probably negligible, in comparison to paying the 15% tax. There's always a loophole. Incorporating a Canadian company is easy enough, especially given most properties tend to already be held through SPVs. In most countries you have to pay local capital gains tax on properties anyway.

To combat holding properties through companies, one would have to look at the ultimate beneficial owner of a corporation, which can often be hard to do / verify.