Well, I'll take a stab at it. I also own a Coachmen, which is FR.
The expensive stuff inside are commercial items. Microwaves, inverter/chargers, heating units, refrigeration, jack knife couches, etc. Same with most of the outside stuff, like A/C units, axles and wheels, propane system components - they're all made by someone else, and most brands are using the same units from a relatively small pool of manufacturers.
The differences would show up in how the wiring and plumbing are executed, how well the walls of a TT are made*, the quality of windows, cabinetry, and documentation. The documentation for my van is just a pile of manuals in a bag. But the cabinetry is actually pretty well made (Amish craftsmanship? <shrug>
). They didn't bother to plumb in a bypass loop for the Truma Combi furnace/water heater unit, so I did it myself. It would have been nice to have a remote panel for the Xantrex inverter/charger rather than a wifi app on a computer, so I added it myself.
There aren't many other things I need to do to 'make it mine', as it does everything I was looking for a van to do, and DW is happy which is a super big bonus. They could have
upholstered the inside of the back door like some (but far from all) brands do, but I pull the shade when parked for the night and can't see it anyway. Picky stuff like that. And I don't want to pay even more money on what's already an expensive unit for its size for picky stuff like that.
But do be aware that, if you're planning on using it as a hunting lodge or otherwise use it in cold weather, it's a 4-season trailer. The tanks and exposed water lines will freeze and you won't be able to use it, plus those parts will break which can be a tremendous effort to correct. I winterize my van and take it on trips in the winter sometimes, but I leave it winterized until I'm far enough south to start using the water system.
I rewinterize it on the road on the way back when it's forecast to get cold, but I'm set up to do that easily; the van's water source/destination selection valve has a position for sanitizing/winterizing, and it'll just suck RV antifreeze right out of a gallon jug using a short nylon hose with standard 3/4" male hose end on it. Lots of people do this, but I had to make the hose and test it at home so I'd be ready to do it in some RV park or Walmart lot on the road.
*I know nothing about TT walls, by the way, but from what I've read, there are differences. The closest I've ever come to owning a TT was a pop-up tent trailer that I stripped down and made a motorcycle trailer out of, long ago when I worked in a scrap yard.