Enclosed trailer.

Ok I?m getting an itch to get an enclosed trailer to do a mini toy hauler and sleeper conversion. Goal would be to have a small off road or dual use motorcycle, my paramotor (basically a 2?x4.5?x4.5? brick), a place to sleep and enough storage to not have to load my suburban constantly. Based on some rough sizing I think I need about 70 square feet of space. This is not a portable home and I am not looking for extreme comfort. Use would be to go for meetups or 2-3 day trips, and have it ready to roll with minimal packing. At campsites the motorcycle would come out. I would like to limit it to 3000 lb total so it?s towable with a Maverick or other smaller truck.
I watched a bunch of YouTube videos but there are a few things that I am not sure of. I was wondering if any of you have small trailer experience or enclosed trailer experience and what you would recommend. And let?s face it the knowledge on this forum is excellent.
For instance here is some things I am still working through.

Aluminum vs steel? Aluminum is not much lighter.
Do they rust a lot? Will aluminum last longer?
Side and dirt roads, do I need an off road package?
Ramp vs doors, with one or two motorcycles I can bring a small removable ramp or is a drop ramp the way to go. Which setup is better?
Is 0.030? skin really better than 0.024??
Is rivet less construction important?
Anyone have experience with a walk on roof? (It would be neat to have an upper deck but not sure it?s worth it?
7 foot vs 6foot width. Is 7 foot that much worse to tow? (7 foot by 10 foot long might be perfect but not sure about the additional width)
Any experience with modular interior setups? Going with my son and two motorcycles for a trip would be easy if the interior can be reconfigured.
Any other important things to look for?

I would make sure there is a side exit door trying hop over stuff to get to the tounge area is a pain

On a small trailer the expense of aluminum isn't worth the small savings.
If they salt the roads where you go it will have an effect on the frame.
Ramp is better. Bring extra motorcycle stands or get the cable kit and use it as a deck. A not so muddy space is premium.
Skin doesn't matter. Rivets are leak points for water and air.
Walk on decks are not usually built well, also don't risk your waterproofing like that.
Try to match the wheel width of your tow vehicle, it will whip badly in ruts if you don't. Also look at your mirror width and don't get a trailer wider than that
I advise to get a happijack bed set. That's the brand name of bunk beds on tracks that go up in rvs to clear the toy area.

As dfbrews said but make sure that door has rv handles. Get a window on the opposite side for egress and cross flow. Put in a good vent fan not the junk cheap ones. Get a fan cover. Find a low profile chalk mount, preferably flush. Add 2 Co/fire detectors. Bring a fire extinguisher mounted. Insulate the thing. Get one with brakes. Ditch the Chinese tires that will undoubtedly come with it and buy Goodyear. Get a spare and a bottle jack onboard along with a wrench.Get ez lube hubs. Electric tounge Jack's are usually worth it. Get rear stabilizers so you can load and unload unhitched. Try to include things that will save you time and frustration

I would spring for extra head height so you can insulate. Also v nose does help some with towing and gives you room to do a built in cabinet for misc gear.

Check out DCA for tie down ideas.

Well I am pulling the trigger on a 12x6 that has been done by the previous owner. Heat and solar is done and the cost of a trailer and parts would be more than this thing.
I kind of wanted a 12x7 single axle so I could place the bed up front but this is done. Since this year has about six major kids life events plus work is bonkers, I decided to buy not build. In other words I doubt I would have time to build one this year.
So this will be proof of concept and might turn out good enough. if not i will build something in a few years.

Just need to equip the inside a bit snd I'm gtg