@Gina I assume you have the right driving license for these things.
Those are essentially converted delivery vans. Generally very reliable, but everything hinges on the engine. Look them up, get one that runs half a million km, not all do. The rest is just a box that should not leak and have the conveniences you desire (bed, galley, toilet, the showers suck anyways). It will break and you will fix it or pay twice for having it fixed.
You got the rest right, part fun adventure and part ghetto and a bonus part of "you can't stay here we're calling the cops".
And getting very excited about finding a manhole you can pry open with a hook so you can dump your toilet tank into the hole without having to carry your collected excreations around in a sloshy tank.