I have one.
The pics in previous posts appear to not be FEMA spec trailers. They look to me to be trailers off of dealers lots that were re-purposed by FEMA early on. Those are the choice campers to have because they will have all of the tanks and a camper refrigerator. They removed the TV, Radio and luxury items in some of them. i have only been in one when I attended an auction.
I purchased a FEMA spec trailer. these were built to FEMA specifications. They are very basic and will not have decals or awnings when viewing from the outside.
They smell/vapor issues in my experience have been hype. I seem to be the only vapor issue in the camper
Mine and all of the ones I have looked at (100+) have DC power, lighting, propane heater and water heater (10 gal in mine), shower garden tub combo, microwave, foward queen bed, two aft bunks, futon sofa(RV type and cheap), galley table/bed (RV type). The difference is that FEMA spec campers have a porcelain household toilet, household refrigerator, and no fresh, grey or black water tanks. The grey lines and toilet lines converge at the side of the camper and were intended to be connected to existing sewer systems. I added a RV valve to mine and I pipe to a 42 gal blue tank at my hunting camp. I also run a generator. I did add a fresh water tank and pump into the system. I works great but I found I can monitor water usage better by just filling the back of the toilet as needed.
I posted pictures on this Forum about a year and a half ago, just search for FEMA, they may still be active.