I don't disagree with anything you've said. I'm very familiar with RVs (I've been living and traveling in a motorhome for five years), and their limitations. And, you're right about shipping containers, generally speaking. But, I've met folks over the years who have successfully built a modern, energy efficient, home inside of the shell of all of these things, often with reused components (though insulation is one of those things that degrades with age and has developed dramatically in effectiveness in recent years, so it's usually new). And, of course, energy efficient appliances are a relative new invention; so they're also usually new. So, re-use is much more limited than I'd like.
I also know some folks who've built tiny houses on trailers; this one is 10x10, which makes it not street legal. It'd need a wide load permit and a good travel plan, in order to move it. I like the idea of an updated RV because I could haul it with my truck, even if I'm not regularly traveling with it (I'd rather have a motorhome for regular travel). But, many tiny houses built from scratch also have that property.
There are trade-offs in any construction. I probably should just say this is not the house I would build, when I build a tiny house (and I will build a tiny house, at some point). There are several reasons why it isn't.
And, speaking of re-used vs. newer/better materials, I've become somewhat enamored of structural insulated panels. There are a couple of folks who've built tiny houses with these materials, getting them custom cut for their needs, and it's pretty cool to see how fast a house can go up, and how efficient it can be once built. I don't know if I'll got that route, either. Compromises all over the place...
