That's where my heads at (and what I was trying to allude to with post #92). Gamify it, where I post something and in order to respond with something politically motivated people have to pay $5/post.........with some people drinking on here and taking their politics very seriously, you could make $100+ from one person in a night. My company does this kind of thing (setting up storefronts for people to sell custom clothing). It's all drop shipped and printed on demand so there's no inventory risk. Buying in bulk and shipping them out yourself is a fairly antiquated business practice in custom apparel these days.
Paying for classifieds on here would never work. Yes this is a huge avenue for parts and bikes but the free market of posting to Facebook/ Facebook groups would take over. Imo Look at EBay and how Craigslist and Facebook market place killed it.
Oddly our paid classifieds site worked great. Wasn't a huge amount of income but it was enough to cover the power bill at the office usually.