Mixed developments for which a "poor door" makes sense are unnatural because they force different people together. I have enough trouble in a medium apartment b

Mixed developments for which a "poor door" makes sense are unnatural because they force different people together. I have enough trouble in a medium apartment building with divergent interests between people owning very similar apartments on different floors (different heating expenses) or on different sides (different trouble with trees and other properties); I cannot imagine a place with different people getting different services. The solution? Drive moderately rich people out of the city with brutal taxation of luxury homes (according to building types and straightforward measures like residents per total area of the property).