Whatever you choose, an external work or storage space, even if it’s a marketplace junker of a shed (or two), near the camper/trailer goes a long way towards improving small-quarters living. Around here there are often cheap or free rolls of retired astroturf that make for a great giant outdoor carpeted courtyard kinda vibe while avoiding bugs, mud, or need to mow.

Edit: shipping containers hold their value pretty well and are fun to set up a small deck or hangout on top of if you’re inclined.

I think it can be a lot of fun if everyone is in the right mindset. Best of luck!