Your little Skamper is a simple base type pop-up. I was referring to the fully equipped slid-in from Europe that was pictured. It appears to be fully loaded, but from what I can see from the video, looks like its made from a fiberglass shell, which is very simple to line with insulation and an inner shell.
Stuff made here still uses construction from the 60's and 70's with framing, studs, bracing, ect.
I've seen some European rv's at shows, and it puts our products to shame, both in materials used and construction quality. I wish their products were as available as their cars are...it would put many of our rv manufacturers on notice.