Seriously.
He's locked himself in a dark room
He always wears a dark hoodie, day or night, warm or cold; down low to hide his face.
He has weird marks on his face.
He's always bartering random stuff, that nobody that looks [i]that[/i] homeless should be able to afford. And he won't say where he gets it.
Nobody ever sees him come or go. Ever...
Those "drives" he sells, kinda look like the novelty lighters, you buy from a glass shop...
He sells needles.
He's tweeking. We need to stage an intervention.