I think this could be a trillion dollar industry. Make government buildings or every building really reusable. That is. Walls and floors are detachable for other house projects.
Basically you don’t destroy anything when pulling down a building. But you probably have to adapt building methods for this.
Perhaps inspiration can be taken from modular housing. But here a modular and reuse interior strategy. For example. Why could not office chairs and tables look as if they could also fit in a home. Saves money.
Infrastructure is expensive so the idea is to make architecture reusable. This way costs can be kept down.
At the same time it would make it possible to create more affordable homes for homeless and connected risk groups.