@Barbara542 the deposit is not ever collected unless the guest agrees to pay it. It is not charged at booking. Hosts do not have it in an escrow account somewhere and return it if all is well. Airbnb does not do this either. All it is, if its anything, is a possible deterrent to guests who might want to throw a party or do some other heinous thing to your space. They may believe that they will owe up to the amount you list. But in reality? If the guest doesn't 'fess up and agree to pay, well, you are own your own. I suppose Airbnb *could* side with you and take the guest's money, but I think I have read that they need express permission to debit a guest's account. Maybe all they need is enough proof? I dunno. I have gotten different stories from different CSRs.
Many hosts here have a story about damage that the guest refused to pay for. We are often left holding the bag. Unfair? Yep. But that is the pond you are swimming in.
From the TOU:
Host-required security deposits are different from Airbnb-required security deposits in that no authorization hold will be placed. Guests will only be charged if a host requests to collect on their security deposit. Depending on what was damaged, the amount the host requests may or may not be the same as the security deposit.
If there’s an issue during your stay, for either Airbnb-required or host-required deposits, the claims process will work the same. A host can report an incident and submit a request for some or all of the security deposit within 14 days of check-out or before a new guest checks in—whichever is earlier.
And in the claims process, the guest can agree or disagree. Airbnb could theoretically side with a host, but in my experience, it does not happen very often.