I recently bought a hybrid trailer and also found the mattress was definitely not enough. I also found that I felt the cold air from below so I purchased a couple of foam camping pads and placed them below my mattress to insulate. This worked great and then since I had a couple 2 " memory foam mattress covers I stacked 3 on top of each other and covered them with a fitted mattress cover which helps them stay in place. when I am done I roll each up and store them on the folded down dinette area. I sleep great, and no aching hips or back when I get up. Getting good sleep is worth purchasing memory foam and it stays in the trailer when I am done traveling.
