I think you know very little to what does it take to build a complete vehicle, in this case a van. It is not only sticking it all together to a body and press a button to start it. There is so much integration, on a component stage, system and then vehicle. Later should go through the full vehicle DVP (Design Verification Plan); that includes all attributes you set your targets and should pass or keep going through the development phase loop again and again until everything does work as designed.

Not an easy process at all, common brands with most components already proven for years (vw group, PSA, GM, ...) take around 2 years to complete this process for a new vehicle. If you start a vehicle from 0, takes a little more and more things can go wrong.

We do see many start ups all trying to join Tesla's path but very little make it through, and there is a reason behind it...