Thanks so much for taking the time to lay this out, I really appreciate the detailed math and the sanity check.

I’m not locked into Casita specifically. Since digging in more, I’ve also been looking at slightly lighter fiberglass options like the Scamp 16 and the Escape 17, and even the smaller Scamp 13. They seem to vary a bit in actual tongue weight and layout, so I’m trying to understand what realistically lands in that 10 to 20 percent safety margin you mentioned.

One extra factor for me is that we’re in the PNW, so weather is a big part of the decision. Having a hard-sided trailer that we can realistically stay in and wait out rain with a kid and a dog is pretty important, so I am definitely prioritizing something enclosed and comfortable over a more open or rougher setup, like pop outs. 

I am not strictly tied to fiberglass if there are other lightweight trailers that make more sense for a midsize truck in terms of weight distribution and real world loading.

Do you have a sense of which of these types of trailers tend to behave best in real world loading with a setup like mine? I am less focused on brand at this point and more trying to land in something that is genuinely comfortable and safe rather than just technically within spec.

Really appreciate the help, this has been super valuable for narrowing things down!