We have a villa booked in France next year. The cost is £2300 for 10 nights. Me, DH and DD. My sister and her family are also going. They are in another villa so there will be a mix of family stuff and doing our own thing. Sister and I have a mutual friend who might like to come for a long weekend with her DH. We have space and can accommodate them in our villa for 3 nights. What contribution to the villa costs would you take?