So their role is increasing the scarcity/cost of property? Remember a landlord is not a developer or builder - they generally buy property that already exists.

So their role is increasing the scarcity/cost of property? Remember a landlord is not a developer or builder - they generally buy property that already exists. I think what you are saying is that the property wouldn't be available to rent, BUT would be available to buy at a potentially lower price (as buyers wouldn't be competing with rent extractors/landlords)? I know we are talking commercial property here, but look at the market in Sweden, where renting property to live in for more than a month is illegal in most cases. The cost for a young person to buy their first flat (often with family support) is low. The country operates fine with very limited rental. People still build property, young people still get to live.