a) There's nothing unique about the signing process for Airbnb -- you can use the same method with other channels like TripAdvisor and booking.com that give you the platform email to send a signature link and get the real email address and the signature.
The only thing unique about Airbnb is they include that email address on the iCal -- the other channels need API integrated or channel bridge to get that email.
b) The signature process via the trigger and {BULEASE} link is exactly the same as if you went to a booking's Legal tab and did a request e-signature. They'll enter contact info and sign, and then the signed .PDF is emailed to the guest, to you, and stored on the booking's Legal tab.
Normally folks only require the responsible/booking individual to sign, but you can send multiple links if you want.
c) You can query the booking List to see booking date and whether the agreement is signed. You could also create a reminder template/trigger to yourself to follow up if they haven't signed in a certain period after booking, and then contact/cancel as needed.
