Hmm. I'm not sure about the mounts/vehicles option, but otherwise that's probably not a bad way of doing it.
Older versions of the Robe of Useful Items had (IIRC) a mule in them.
And a lit campfire. LOL
Not sure about the current one.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.