I assume that the proposed tax would be a surtax payable annually.  

I agree with others commenting on this article that such a tax doesn't target foreign speculators.  Better yet it would target any Canadian or foreign resident that is not paying BC income or corporate tax.  Not only is this more equitable but it also negates potential legal challenges based on the Charter of Rights and Freedoms or a wide range of Free Trade Agreements to which Canada is a party and which give individuals and corporations resident in Canada's trade partner nations the right to legal redress with compensation against Canada if a law in Canada denies them equal economic advantage to that enjoyed by Canadian residents.

One question I would like answered, however, is how the NDP proposal would dovetail with the surtax that Vancouver City is instituting.