Thanks! All are good points, and several of them things that we're planning on doing e.g. SSL, encrypted SSNs with a note reminding users, email notifications.

Thanks! All are good points, and several of them things that we're planning on doing e.g. SSL, encrypted SSNs with a note reminding users, email notifications. Would you mind going further on why would it be a good idea to let communication with the broker happen on the site. In general, I get annoyed at the re-implementation of email (e.g. facebook messages) when it is not absolutely necessary (the messaging system on airbnb, however, makes perfect sense).