My son has let his basement to a father and son , but it is just till their place is renovated , they have their own shower , a toaster and kettle , think they have to use the kitchen . They are all good friends , so we will see if they are still friends in a couple of months . I had my sister to stay while she house hunted , she took over both spare rooms and it was a bit fraught when the uni hols came , she of course was oblivious . We are still speaking some years later . I have room but can't imagine house sharing ever again