Doc those little trailers are cute but I think a 4x8 is far more versatile. It's not much wider, mine has the same outer width as my Subaru so will go through anything the Subaru will fit through.
When I'm harvesting apples to take to friends in town I pull the trailer with the tractor and pick right into it, then come back to the barn and hitch it to the car. No double-handling of the apple bins. Or bring home 3/4 ton of sand/gravel/mulch. Or new toys I found on Craigslist.
Taking the same trailer offroad and on the highway is a huge advantage. Using one trailer for everything cuts down the need for maintenance, and for covered parking.
Cost for this one was a little less than that one, and its capacity (volume) is triple. The tractor can drag it across rough ground like that guy going over boulders. Single axle is easier to turn around by hand when its not hitched to anything. It's only 400 lbs as flatbed or 500 with sides.
That little one is cute, but for me I don't see a need to own a separate specialized piece of equipment for every different task.
Here are a couple of photos I've posted here in the past.