Canada

Any property that you put up for rent is actually treated as a business by the CRA.

• You pay higher property taxes on a rental.
• If you sell, and the property isn't your primary residence, you pay capital gains taxes.
• All rental income is taxed and you can't claim that rental income... you can claim interest paid one the mortgage, but it's not that much.
• There are incentives to maintain a single home when you're buying and selling... If you buy/sell your primary residence you don't pay capital gains taxes.

Should there be more taxing on second and more properties that are investment... maybe. If you increase the cost of ownership, that cost is placed on the renter. A property owner isn't in the game for fun and they aren't going to be willing to take a lot just for the benefit of a renter. It might put pressure on speculators to increase the taxes, but... It's not as 1:1 as people like to think.