I know this topic has been an issue many times but now I have taken it upon myself to overcome this .
Once an enquiry comes through and shows a free infant attached, I immediatly contact the prospective guest and let them know there is going to be an extra service fee for (each) the infant that will require additional sleep area, additional bath towels , additional rubbish removal of soiled nappies, additional heating/cooling additional notification to neighbours to allow for possibility of crying child in the midde of the night etc, and this charge will be an additional $100. or they can just register an additional guest for the meagre sum of $18.00 per night
Then if there are more guests than my home is registered to sleep I can decline the booking as not being suitable as insufficient bedding.
No back lash from ABB then as Any one can cancel or decline a booking with no recourse if the number of guests exceed my max numbers allowed.
This has worked when I had an enquiry with 9 adult guests then later during initial contact found out that there would also be 3 infants for free.
My home is only suited to max 9 guests.