There's not much you can do, beyond the crude tool of affordable housing intervention, once the land value goes up.
Barring the invention of a time machine (go back and build the units you need today!), I think that one possible forward looking solution is to encourage the development of units on land that isn't high-priced yet. In other words, preemptively lower the regulatory barriers to development in areas that aren't already hot.
Problem is, politically, it's only after areas get hot to develop that enough pressure forms to get cut through the red tape. And, when a developer does manage to get through, they would rather put the barriers right back up to prevent competition.
Barring the invention of a time machine (go back and build the units you need today!), I think that one possible forward looking solution is to encourage the development of units on land that isn't high-priced yet. In other words, preemptively lower the regulatory barriers to development in areas that aren't already hot.
Problem is, politically, it's only after areas get hot to develop that enough pressure forms to get cut through the red tape. And, when a developer does manage to get through, they would rather put the barriers right back up to prevent competition.