I'm sure the weight of everything in the conversion of this van doesn't exceed the rated load capacity. All that stuff isn't really that heavy. It can hold a lot more, and still probably has enough oomph to pull a trailer.

This is still classified as class C automobile in America, at least. An ordinary car that requires an ordinary license. If be surprised if the whole thing is 6000 pounds with everything installed. There are some big cars at that weight.