LOL (and I don’t use that “term” often) - this is one of those less-than-likely to be fruitful posts, but I guess it don’t hurt to ask. And it’s creative - gotta give it that.
For the OP, here’s why no thinking person would agree to this: The owner would essentially be “renting” the coach to you with the rent being your time and expenses moving it from LA to Chicago (assuming anyone would actually want that which is a longshot, but…see above).
So then you have a rental contract, verbal or written, which at best turns in to a month to month agreement at the end of the term of agreement. If the ”renter” decides not to relinquish the domicile (because thats what it becomes), best case scenerio is 5-6 weeks for an eviction (because thats what it would be), and then only of the laws in Illinois and Chicago allowed that.
Then throw the anti-landlord Covid policies into the mix, and you have a very unattractive proposition. And of course that doesn't even start to address all the other risk, logistics, and potential wear/damage issues of the idea.
So while it doesn’t hurt to ask as I said above, it seems very unlikley that you’d find anyone with a suitable motorhome willing to risk it all and enter into an agreement like this. But its an interesting proposition…