Hi again.
I don't value bikes, since value is a subjective assessment (ie, they are worth what someone will pay for them) and it has caused me grief in the past.
I can tell you that the frame is the more desireable Balloon Tyre version (there's a narrow tyre version too), and by itself would be $200 give or take, but it is nice, so possibly a bit more. The lining and paint job are non standard, non factory, and since they seem to match the N°29 on the tank, were probably done when it was converted.
The motor modification is something I know nothing about, how much value it adds, or whether someone would buy it to transfer to another bike. I suggest repeating your request in the Motorized Bicycles section here:
https://thecabe.com/forum/index/motorized-bicycles.30/
Also, to avoid confusion, although it says 'Paratrooper', this is a sales gimmick. It's not actually a paratroop bicycle, although bikes of this type were supplied to the military during the WW2.
I hope this helps,
Best Regards,
Adrian