@Joe2154 when guests break No party Rules don't negotiate by asking money just ask CS to ask them to leave. or you will call the Police.
When guests think they can have their way out by paying extra they will do it again, but if they are aware they will get kicked out they will think 2 twice.
I closed my eyes on small rules like bringing 1 extra guest but not on Party Policy/Noise Policy
Airbnb sent to hosts this week a link to Minut (https://airbnb-eu.minut.com) as Party Prevention tools u should have a look at.