My boy's a teenager

Okay, so he wants to move into the basement. Okay, fine. He also understands that our basement is an OLD basement with low ceilings and poor layout. Our house was designed with a basement for storage, not comfort. He is aware that he will be sharing his new "space" with storage... Of everything that is down there. I have gone through and emptied boxes, thrown stuff, recycled magazines/papers, donated stuff, and put stuff away. He has tons of toys when he was growing up.... And now he is willing to go through his stored shit and clean it out. He is purging his stuff. I guess I can move forward with him moving downstairs. If he can clean his stuff, find room in the basement, and then move his stuff downstairs, I get my room back and will have my own space that I haven't had for over 16 years.,