Hey Morgan,
In the community you won't get a response from Air BnB, instead you'll get responses from other users (like me). If you charge the fee inside Air BnB, you will be subject to Air BnB's 3% service fee. Since the additional services are not really tied to Air BnB, I'd recommend charging them outside of the system.
If you do want to charge inside Air BnB, just send your guest a special offer (found on the left side) of your message history with the guest. Be sure to manually add in any cleaning fees, since the system doesn't automatically add them when it's a special offer.
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