Good grief, some of the horror stories on here beggar belief, and make my problems look minor.
I offer up the following (rather less) salacious offerings:
AP (age 22) arriving with hand luggage only (HINDSIGHT ALARM BELLS) and then refusing to do her jobs after day 5, but thinking she could keep living with us for free and eating our food and just do bits and bobs of work when she felt like it. Like an hour every day or two, or something. If she could be bothered to get up. Er, no. We are not your parents and surprise, surprise, we do not have to house and feed you for free if you want to opt out of all community responsibilities.
AP (19) being delivered by her mother (HINDSIGHT ALARM BELLS) with two massive suitcases, and then more or less lying in bed for a fortnight skiving off. She then decided she was going and rang some friends of her mother who live near me and whom I had briefly met, and much to their surprise announced she was going to stay with them for a three week holiday 'as she was so exhausted'. They refused on the grounds that they were not a hotel, but said she could go over there for a day or two and then go back home once a flight had been booked. On the day she left me, I got up, got the kids ready, and was ready to leave for work at 8am as usual, and she was not up. I knocked on her door and she was asleep. She eventually surfaced and said she didn't feel like getting up and she was going to have a leisurely morning and surface about 11am, and make her way to the other house around the middle of the day, while I was at work. Shall we say I disabused her of the idea that I was going to leave a relative stranger with a work ethic problem to lock up my house in my absence, and within 30 minutes she was in a taxi to the other place with all her luggage. To her credit on the driveway, she said, "I haven't been much help to you really, have I?" I suppose for her that was the first inkling of self-awareness she had ever had.
AP (19) who told me after about a week or two that she was so depressed she was having fantasies about being in a bus crash and dying. My kids were something like 5 and 8 at the time. Yikes!
AP (23) who was very weird, probably stole 90 euros from me with hindsight, sat in a darkened sitting room with the kids day after day watching DVDs for the entire gloriously hot and sunny summer holidays unless I was physically there to prevent it, and after we left a package arrive with some fairly sicko Harry Potter porn fan fiction arrived with what I thought was my name on it, but with hindsight was probably addressed to what was her writing nickname by someone who didn't know she had been sent home. I was phoned up for a reference shortly after the arrival of the package and I gave her a really scathing one, as it was clear by then she was really dodgy.