I think it's important to establish communication with guests, to ensure that they are responsive in the event I do need to contact them. I'd like to leave the instant book setting on, but no communication from guests makes me nervous. The Pre-booking message seemed like a viable option, so I reached out to Airbnb Customer Support to understand better on how it works. I had concerns if guests see this message BEFORE they instant book, or if they simply see the message after the booking is approved?
What I got to know is : When you enable the pre-booking message with Instant Book, the guest will receive the message as soon as they reserve. The reservation will be in Pending status until they reply, to which they have 24 hours to respond.
So, technically they are pre-approved until they respond - pretty simple. I think it's a great way to make sure that you've established communication with the guest, while still allowing them to Instant Book. To learn more about Instant Book, you can also refer to these help articles : Everything about Instant Book.