"The shape of the fusalage seems quite complex, might be difficult to make."

"Shouthampton University have been looking into this sort of thing. They have flow a UAV that has been made on a 3D printer:
https://www.youtube.com/watch?v=JsD7qo7X3eU"

"If you can get a hold of "Airplane Design Part I - Preliminary Sizing of Airplanes" by Roskam there is an equation in there which you could use to get the empty weight form the take-off weight, if you get some regression coefficients from existing…"