My 18yo DD has been seeing a 28 YO for about 4-5 months which I'm not best pleased about and therefore she's kept him away from the house. Apart from when I've been out and he's clearly been in the house smoking out of her bedroom window, stubbing his cigarette ends on the wall outside leaving a nice black mark and me having to pick up his cigarette stubs from the garden. I had a moan at DD about this and made her clean the wall. So already I've taken a dislike to the guy for disrespecting my home. I've had a text from DD today asking if I'll ever let him into the house. I've not responded yet because I'm finding it very difficult to accept. I'd like to sit down with her and lay down some rules if he is to come round, ie not stay the night but she'll probably disobey me anyway because her previous boyfriend practically moved in during lockdown. What would you do?