I like my KZ spree. I think its built pretty well. But I have no clue what new costs. They do have things like this:https://www.kz-rv.com/products/sportsmen-classic-travel-trailers/160QB.html
But that may be at your upper limits. Remember that also, while you are within your tow limits, the weight and height will cause you to not accelerate as fast. Or stop as fast. Its a big brick, but you know this allready. I would look for something like the link above. Seems like that what you want. If you can find it in a smaller package that would be nice. But I think if you get to smaller, you will have a bed that needs to be transformed. They have a smaller model, but with the sofa bed, and with that you dont have your space. This one is sort of a compromise.
But that may be at your upper limits. Remember that also, while you are within your tow limits, the weight and height will cause you to not accelerate as fast. Or stop as fast. Its a big brick, but you know this allready. I would look for something like the link above. Seems like that what you want. If you can find it in a smaller package that would be nice. But I think if you get to smaller, you will have a bed that needs to be transformed. They have a smaller model, but with the sofa bed, and with that you dont have your space. This one is sort of a compromise.