Related, maybe an area to expand into: I've always thought an "AirBnb for RVs" made sense. How many people buy RVs, use them for a while, then let them sit for 20 years while they devalue? Just a thought.
Or RV Swaps, like house swaps. For either other side of the country or another country altogether. I've had that idea for a long time hoping someone would do it.
Insurance and others is a minor sticking point I think, but should be workable. On the plus side, unlike house swaps, they don't have to be simultaneous.
I'm always curious how side-projects that are marketplaces initially got their supply. Seems like there's a good amount of RVs listed, did you have to do your own biz dev footwork in addition to building out the site?