I have found that if something goes wrong with a booking, it is usually the host that suffers any consequences - you lose your 'Superhost' status, or you are penalised in some way. But guests also jerk you around, with no consequence. I recently had an enquiry, where a student wanted to come and stay for two months. Because it was such a long booking, I offered all kinds of extras for free. She then asked if she could book for one week initially, to see if this was a comfortable fit. As that kind of decision cuts both ways, I said yes. Time went by, she did not confirm the booking or pay. The booking was still provisional. Day before she was supposed to arrive, I asked if she was still coming as I would need to prepare the room for her. Oh, she had found somewhere else. Sorry she did not let me know! Now, I would like to warn other hosts about this person, as this is bad manners. But there is no provision to do so. While her booking was pending, I could have lost other bookings. Why can't I report an unreliable person like this?