@Caleb45 @Clare0 @Inna22 @Branka-and-Silvia0
Caleb, your agreement is between Airbnb, yourself and the host!
It is up to the host to make sure that any third party interests are disclosed in the listing description.
The host is quite entitled to ask for card details to cover 'unforeseen' circumstances....City taxes, special guest requests but, only if they disclose these additional amounts in the listing description prior to booking. Airbnb do not encourage third party transactions and any security deposit should be edited into the hosts 'Extra Charges' so they will be clearly displayed before a reservation is confirmed.
If your host, or the hosts agent has subsequently required additional sums of money that were not prior disclosed it was up to you to either cancel the reservation or accept the additional charges for the sake of the stay but, once the stay has ended and your additional money has been returned, flag (report) the host for operating outside of Airbnb's rules!
I hope this is of help to you Caleb, and all the best for the upcoming year!
Cheers......Rob