So I just want to know the size of an aircraft with a lifting body that would fly at low altitudes (around 40 meters/100 feet), and at low speeds (maximum 200 km/h 124 mph). But I don't know if these numbers are even useful to the question.
I tried to search for more aircraft like that, but most of them just fit a single person (the pilot).
I did find some illustrations from reentry lifting body aircraft (like the Martin X-23 Prime), but I can't tell if they are 1:1 or simply an illustration.
I did find the Wainfan Facetmobile FMX-4 quite simple and interesting, I don't know how fast and how high this aircraft can fly, but I think it could be a simple way of scaling things up.
I found this video of the FMX-4 showing its frame and engine (and other stuff), I don't know if it will be useful, but...