@Catriona51 Yes, that thread is essentially what you are asking, it seems like to me. Ways to charge less for less guests in a way that is clear and results in you not having the same amount of cleaning to do as if there were 8 guests.
Yes, some hosts have had guests arriving with more than they booked for, assuming they could have as many as the max guest count (or pretending they thought that). If you don't want to go the route of having more than one listing with approprriate pricing for various numbers of guests, you can put wording in your listing to the effect that all guests must be accounted for on the booking, that extra guests not on the booking, even up to the maximum, will not be allowed on the property.