HIn different thread, it was mentioned that a couple of hosts had guests stay in the rental & their friend(s) stay in a van or pickup truck camper in the driveway/parking lot.
Check out this article. People can get creative.
“…And it’s now legal to crash-out anywhere [inside a vehicle] in San Diego, so it makes more sense for tourists on a budget to rent a 2-in-1,” Michael added, “and sleep by the beach…”
There’s a guy across the river from here who rents out his 5th wheel camper unit in his back yard – runs a power cord from the house when he needs it. And at the marina where my boat is we have two owners who Airbnb their boats and go stay ashore when they’re booked. I would too but my boat is too small…
I’m familiar with what you are describing. This is an old van you park on the street-on any street instead of in the owners yard or property.