It does look like a kit, although the hub motor pressed wheel matches the front which suggests the two wheels were bought as a pair, or possibly it was manufactured as an ebike, although I doubt the BMW branding is genuine.
Standard bottle battery with a separate controller - the white box under the downtube.
In terms of salvage, the key thing is if the motor and battery works.
With an ordinary spoked wheel you could replace the motor.
Of course, you could put an ordinary motor wheel on it, but it would look a lash up.
The battery may or may not have any life in it, about £300 to replace.
The bike bits are cheap and cheerful, but presumably standard.
I reckon the bike as it stands is worth nothing, but could be a project for someone as a gift.
Incidentally, BMW do market a branded ebike.
It has the Bosch motor and can be had for under £2k, which is competitive in that market.
https://www.bowkerlifestyle.co.uk/b...=3c26f95ec43bf67a5018771cc9459d68&fo_s=gplauk