The best hamper?
I have a plastic one I bought at Walmart. It has wheels and the handle extends.
look for a small wire cart, floor level, on wheels -- these are often sold for grocery use but should be plenty sturdy for laundry as well
I agree with Rebecca, I use that kind also.
A mesh bag, and you can put your powdered or liquid detergents in hermetically sealed plastic containers that don't have sharp edges so you can put the whole thing in the washing machines.... If they are "front loading" machines, make sure they are low-sudsing detergents.