Me, I have a very small collection, mainly wild west and now a small zombie apocalypse/ modern adventures. I have always kept my collection small, I've dabbled in horror/ sci-fi genre, mainly because of limited storage space but also if it doesn't see table time, it goes on ebay!
Last year, I rebooted my wild west collection, from 28mm to Heroic 28mm (32), with suitable MDF buildings. That is my sweet spot, I only collect that scale because buildings and scenery works with what I game.
Because I have a small collection, EVERYTHING is/ will soon be painted, no lead mountain laying around taking up space.