That really sucks, I'm sorry. That's illegal, right? I wonder if a lawyer could send a letter as a warning. Then get security cameras? What a headache!

This is the United States

I don't know everything about Dr Luke and Kesha but it's strange that everyone is dogging Katy Perry for working with him, but Doja Cat did the same thing and nobody cares?

Those are the two of hers I read and those tools are very helpful. Starting is the hardest part though. Remember the phrase, "If nothing changes then nothing changes".

Especially before the party, I would stick to the Dana White methodology - start with places visible to guests, fill up a box of items that you can donate (use the container method - if you have a hall closet you can keep whatever actually fits then donate the rest), and then have a set day/time you take to a donation center, like every day at noon. I highly recommend Dana White's audiobooks. There is some other great info about her methodology on this subreddit.