Thirty days after a person moves out is a good amount of time for storing anyone stuff, after that you have the right to dispose of that stuff if it's not picked up by then. If you have a number or forwarding address? Send a written notice and keep a copy of the written note . take photos of the stuff left behind and dispose of it after 30 days.
Is that person legally on the lease? Does that person claimed that place to be there legal residence?
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