I'll ask him for more ideas, he's full of 'em. Another one that he really likes is to build gypsy wagons and chuck wagons using aluminum frames. https://www.woolywagons.com/ This is basically his idea. We made our first one using an old ten by five trailer (one of those small ones without tall walls or a roof) and used aluminum to make a frame, then we took the bottom of a boat and made it the roof, and it is now sitting out by our duck pond. It wasn't that difficult, and people have tried to purchase it from us asking for a price that is waaaay more than the thing cost to make.

Of course, this is less labor than making fences, but more know-how would be required.