IF you absolutely must have a brand new car (why?), especially if it’s an EV, and you do average to high mileage, sourcing via Motability is a no brainer.
If you are happy to run a used EV (but check the insurance cost first), dealers are virtually giving them away (some are as little as 20% of their new cost) as they can’t sell them. Ownership costs would be significantly cheaper than running a new one from Motability.
The issue of EV residual values means that only a fool would buy a brand new one with their own money – even at 0% interest!