single woman wants to join our cottage weekend with three other couples how do we make it work

so were organising a cottage weekend in margaret river with three other couples in a few months and a single woman we all know from a club in perth has asked if she can come. shes lovely, shes been a guest at one of the couples home meets before, everyones met her. on paper its a yes. but ive never done a mixed group with a unicorn in a cottage setting before and i can already see potential issues. like... where does she sleep, is there a sense in which she "belongs" to one couple for the weekend or does she float, is there going to be jealousy from one of the wives if she ends up clicking with one husband disproportionately, does she get charged the same as a couple for the rental or less. nobody at our club seems to have done this in a residential weekend format. how do you set this up so its respectful and fun for her and for everyone