this is definitely happening in NYC. A friend of mine just told me how he was considering getting in on it.

In NYC there's an enormous arbitrage. The cheapest hotel room in the city is $300/night. Meanwhile, you can rent a 1BR apt for $2,500 / month.

So you rent an apt for $2,500 / month and book it out on AirBnB for $200 / night ... and you're looking at a monthly arbitrage of $3,500.

The guy I know heard about it from a friend who's already doing this with 6 apartments ... so he was making something like $18K / month (less the cleaning expenses).