After (and only after) the trip is confirmed by the traveler, make sure you exchange phone numbers, Facebook or email addresses, to make sure you have an easy channel to talk to each other.
We recommend hosts to ask for the traveler’s ticket (plane, bus, train…) at least 2 weeks before arrival. If the traveler doesn’t send it, you can cancel the trip and look for someone else.
We are currently working on other ways to avoid this from happening. You can send your suggestions to firstname.lastname@example.org