e.g a 40K EV will be leased quite cheap by assuming the cars value will be 37K after 3 years ,
I don't think this is accurate at all, a $40K leased car isn't going to have a value of $37K after 3 years. And no BMW dealer on the planet is going to lease out a $40K car for $83 a month. ($40K - $37K= $3,000 payments over 3 years, or $83.33 a month)
For example - a 2018 BMW MSRP $38,695 230i Coupe can be leased right now from BMW for three years - at the end of which the purchase option value is stated as $20,508. And as a lease-return, it will likely be auctioned off to a used car dealership for less than that, and sold on their lot for under $20K.
The 3 year old i3 lease return I just bought retailed for $55K new (Dealer window sticker still in the glove-box). I bought it from an auto broker, who bought it at auction. I payed roughly 30% of the original list price for it, and it only had 9,600 miles on it.
2015 i3 Rex, Capparis White, Tera World, Technology & Driving Assistant, Parking Assistant, Harman Kardon Audio System, 20 inch wheels, EVoInnovate EVSE