Here’s the scenario
Mum and teenage son plan a 3 night trip to Europe. Mum intend her partner and also son’s friend. Apartment sleeps 6 (2 bedroom). Partner invites two relatives.
Apartment can’t be cancelled.
There was no mention of cost split when friend was invited, it has subsequently become clear a split is expected.
Partner and relatives are no longer going.
How much of the apartment cost should be attributed to the friend?