Craigslist allows posting through it's api for housing things, guessing that's how airbnb does it. If you've ever used thumbtack, a marketplace for services, t

Craigslist allows posting through it's api for housing things, guessing that's how airbnb does it. If you've ever used thumbtack, a marketplace for services, they have an auto post to craigslist as well that is pretty interesting.