If he wants to not be in that "lazy, cigar-smoking, top hat twirling capital class" (as you put it - because apparently hyperbole and gross misrepresentation of an argument counts as "discussion" on Hacker News nowadays), he is welcome to transition his ownership of that duplex into, say, a housing cooperative consisting of himself and the other half of that duplex (or - more likely - a cooperative for the land and the duplex's exterior, and retain ownership of his own unit while putting the other unit up for sale - effectively forming a COA, but cooperatively owned).