I use the big tubs from Wal-mart with rope handles, they are much cheaper if you buy them in the store instead of online, just have to be careful not to press the drill too hard when drilling holes in the bottom. Holds lots of soil, and the handles help to move them around. If you get black, they look pretty much like a giant pot. It wouldnt be too hard to make a flat panel for it to sit on with coaster wheels from Lowes, etc.
