Well, I did agree with him coming to the house this weekend in the first place, the fact that he has behaved this way I'm not sure justifies me taking his key back, does it? We didn't agree any ground rules on how he should leave the house or whether he was allowed to ask friends over, until now he has actually been fairly respectful of this house and usually knocks instead of letting himself in. I think I will tell him that I was very disappointed in what he did and that it will not happen again in the future, and then ask for my car key back. Or is that me being wimpy and frightened of his anger?