My teenagers room is the mess he creates. If he wants it clean, he has to clean it. The only thing I really do is to tell him to do a load of laundry when I realize the floor is too coated with clothes, and then make sure he actually folds it and puts it away. Beyond that, his room, his problem.
Homework is never allowed to not be in the back-pack unless he is actively working on it. That’s one thing that works well for us. If he loses a device, then “oh well”, he has lost it, he can clean his room to find it. We do have a very cheap, track-phone, flip phone that can be “activated” rather cheaply if he’s going somewhere and absolutely NEEDS to have a phone and can’t find his. The only other real problem we have had was one day when he lost his glasses. Luckily he has prescription sunglasses as well and could wear those. I’m thinking about getting him some daily contacts this year too, as a back-up in case the glasses get misplaced.