Marv, I love the
Trillium 4500's, but there are a few things to look out for. The worst, (least fixable) is a sagging front curb side. This can be seen, if you are 6' tall, by standing on the tongue of the trailer and look down the flat section of roof, over the door. If the closet forms a distinct high point, in what should be a flat plain, then there is a problem. This can also be seen by putting a straight edge on the floor from the
fridge, to the door. If there is a perceivable sag at the door, problem. The truth is, I have no idea how to fix this.
Another problem to look for is a spongy floor, in front of the kitchen. This may indicate a rotten plywood core. This is very hard to replace. The floor is raised at the dinette. This floor will be spongy, but that is due to the water tank being under that floor. It is covered by a thin sheet of plywood. This is not a concern.
As for hitch height, better too low, then too high. I am just going by memory, you want about 15 to 18" to the bottom of the ball. Hopefully someone is closer to a measuring tape and their trailer.