Thanks for that link.The article has a lot of good info. People should be aware some equipment specs are deceiving. The folding hand truck is rated up to 500 lb.and so are many other pieces of equipment. That hand truck might not break with 500lb on it but unless its on a smooth level foor it won’t move.
As soon as a person has to move a load up or down hill, the amount of weight the equipment can carry becomes less meaningful. The ultimate test would be pulling the load up a long set of stairs or similar slope. I don’t like going over 150lbs, 200lb maximum. A load over that I need recovery time after the move.
I like the design of the game carts. The frames are long with the wheels positioned in the center so the load can be kept over the wheels. Any equipment that has the wheels close to the end of the frame requires an upright postilion to balance the load. This makes the equipment hard to push or pull and if the equipment is leaned back the load transfers to the handles. The single wheeled equipment would be good going through narrow trails but balancing the load is always an issue.
The game cart designs are long enough to support a person comfortably, some of them are 80″ long. It looks like they could be converted to accommodate a person fairly easily. Check this out: http://www.loomansoutdoor.com/products.htm. Someone with the right welding machine could make these by converting bicycles. Specifically designed for moving people. Add a third wheel to the rear for stability just like a runners stroller.