Or the tax money has to be paid by the subsequent buyer.

The CRA recently came after a  home buyer in Vancouver because the seller didn't pay capital gains on the sale of the house.  The seller was safely ensconced in China, so the CRA took the easy route, and simply came after the buyer.

Bet you didn't know the CRA could do that, or that the buyer is responsible if the seller declares falsely and does not pay.

(In this particular story the buyer lawyered up and sued the middle man - the Notary - and the Supreme Court ordered the Notary to reimburse the buyer.)