I suspect that Rivian is not legally able to event rent out these preproduction vehicles. I like the idea, though.
GM was able to lease it's EV1. The primary reason I think they never sold a VE1 is supply of replacement parts.
So if Ford makes a Edsel, and say the sales are really bad, and they only end up selling 5,000 units total. For the next 7 years, Ford must produce certain body panels, alternators, engines, transmissions, and such things for repair of those vehicles during their normal life span. This is pretty easy to do with a Mustang, and other 250,000 a year vehicle volume cars. Yet the EV1, GM would have needed to produce and have available a significant supply of replacement body, frame and other parts for a minimum of 7 years after production stopped. Say you needed a motor speed controller, GM would be required to produce one for your car, should it need one during that 7 years.
What Ford, GM, Dodge do with their first off the line production pickups? My brother got vin number 000065 one year, and leased it from Ford as a employee. My guess is. should they find that the guy installing the brake light switch was doing it all wrong, and the first 60 pickups need to be looked at to make sure it was done right, it is just a matter of calling the mechanic at the Ford plant and say look at trucks 1 to 300 and make sure that brake light sensor switch is installed and tight.
Rivian is offering a job description that reads "You will tow a single vehicle trailer with one new Rivian on it, and deliver that new vehicle to the customer." My guess is they might be using one of the first 100 Rivian vehicles to tow that trailer with the new vehicle on board the trailer. Great way to gather data on how the Rivian's actually tow in the real world.
Some of the early production trucks will end up on the Insurance test tracks, and crash into a cement barrier. Passing these tests, and making sure the air bags deploy, and in a normal car that the fuel tank does not rupture are important.
I would guess that Ford would sell many of it's lower serial number vehicles (just after the change over in tooling) might be more willing to sell them to Hertz or other places, instead of selling them to the public at large.
What Rivian will do? I have no idea. But lets keep hoping they will do it all very soon. . ..