It’s hard to imagine a better example than this:
A natural zoning experiment in Denver: These two homes straddle a 2010 zoning boundary change. The result: The house in duplex zoning converted into two homes, and the other converted into a McMansion that cost 80% more.
Arthur Gailes, AEI
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This is from AEI’s housing supply case study of Denver, by Tobias Peter and Hanlu Zhang.