It already exists and millions of people have been doing it since the 60's, backpacker hostels. I think as a general rule you'd be paying over $2000 a month for

It already exists and millions of people have been doing it since the 60's, backpacker hostels. I think as a general rule you'd be paying over $2000 a month for a private room, but if you're willing to share you can get well below $1000 a month.