While shutting the double car garage doors .....

[Silverlining]

So here is what I would do...put all their crap in one room and you claim the other room for yourself. Then warn them that if the room isn't cleaned out in 1 year or less it is GONE!

I agree with you. Put all of there stuff in one place, (a place for each person). And, claim the other room for yourself.
But, one year. No, No. 2 weeks, then transport it out yourself.