How large are you?
Small- Screw on containers work well. I like the ones that lemonade and fruit punch mixes come in.
Slightly Larger- Small Boxes work great. I ship via USPS, so for some things, I just set up a flat rate box and start filling it. When it's full, just tape it closed, and send it.
Medium Sized- Large Boxes can be cumbersome, so I built some plywood bins on wheels. They're like this, but more "rednecked".
Large Setup: I know of a place that uses pickup beds to store their large quantity items. Some are trailers with an axle underneath, and some are just stationary on the ground. The ones that can be moved are nice for holding your stuff. Just make sure the yard gives it back.
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