I just bought a single axle, 7 X 12, aluminum trailer with a hydraulic tilt, and it is a dream to load and unload. It has a rail around it that is about 10" tall (you need it low enough so the doors clear it), and I put a 2' windscreen across the front to protect from rocks etc. The hydraulic tilt allows you to drive on and off without ramps or any effort at all. I wanted an enclosed trailer for my P1000, but a 7' wide enclosed is way to tight, and an 8' wide is too much for my comfort and for my vehicle. My local dealer had me drive in an out of various enclosed trailers, had me take lengthy road tests, and made sure that I was buying what I wanted and needed. This buying exercise made a huge difference in what I thought I wanted, and what I ended up buying - REALLY WORTH THE TIME AND EFFORT.
BTW, I was going to buy extra bearing in case of road trouble, but instead the dealer sold me a complete hub with the bearing and already packed with grease - $40. Great idea for sure.
I definitely spent extra bucks for aluminum, but I'm tired of messing with plywood floors and/or heavy trailers. I have a mid-sized SUV (Highlander), and the weight of the trailer and P1000 pulls very easily. I think the aluminum takes about 500 lbs. off of the trailer weight. Plus my trailer will sit out in the weather, and I don't have to worry about it. I paid about 2 times what you can buy a decent trailer for, but my trailer is worry free, nearly maintenance free, and light weight. Not the trailer for everyone, but I sure like it.
(Just looked it up - Aluma trailer made in Bancroft IA, model 7712HTilt, 14" tires, www. alumaklm.com. It may sound like a commercial, but I have no financial interest in this at all.)
Good luck