  A commonly expressed concern about the rise of the peer-to-peer rental market
Airbnb is that hosts---those renting out their properties---impose costs on
their unwitting neighbors. I consider the question of whether apartment
building owners will, in a competitive rental market, set a building-specific
Airbnb hosting policy that is socially efficient. I find that if tenants can
sort across apartments based on the owners policy then the equilibrium fraction
of buildings allowing Airbnb listing would be socially efficient.
