I’m going to be honest, I have never done anything like that before. if you want toy sized then i could be of more service, but full sized… i don’t even know where to begin for that. off the top of my head it would be to take a standard electric motor from a scooter or something, then retrofit it to a brand new frame, then cover the whole thing in fiberglass panels and acrylic. I have no clue how much something like that would cost, or how much time it would take to do it. I will repeat my recommendation to take this to a professional, but if you want i can get started on a rough estimate. i can tell you know that it likely to be well over $10,000 for me to do it, and probably over a year in production.
so lets maybe start off with the PC case mods