Point 1: Your belongings belong to you…
and vice versa. Your roommates belongings belong to them. This doesn’t change even if you share everything. Sharing is caring, but sharing is NOT giving. Anything you allow your roommate to use should be returned to you in the exact condition it was given. Anything your roommate shares with you should be returned in better condition.
This means that in no way should either of you make PERMANENT decisions about the other person’s belongings. Nothing should be cut, thrown out or changed in any lasting way. You can ask, but if they say no, that’s it. If you want to cut a rope into smaller pieces, buy your own rope.*
You may not throw out another persons belongings. I don’t care if you think it’s a cheap piece of junk. To them, it’s a kitty litter receptacle that, they spent hard earned money on.*
*Yes, these are real examples.