In the case where they are renting out each room in, say, a three bedroom apt, the landlord is increasing the revenue from the apartment.

That’s a formula being used often now for newly developed, student focused apartment complexes.

If you’re running a private equity fund, those rules will bring the landlord’s costs down, not necessarily the rent. They have to mandate affordable units or the city won’t get them, unless and until inventory outstrips demand.