Air BnB (sleeps 10) has been booked for £600, and has asked for £120 towards the cost as there are 5 adults who agreed to the price and number of people going (600 divided by 5 is 120).
The organiser has then invited his 2 adult children without asking anyone. The adult children both work full time, and they aren't being asked to pay or contribute their fair share.
£600 divided by 7 (7 adults including the 2 additional host children is £85.71).
The host is still asking for £120, so the remaining 5 adults are expected to cover the contribution of the organiser's children.
Is the host being a CF?