We use Large Plastic bins that we get from American Van.

They have many sizes and they are customizeable by using interlocking dividers.
These things are very durable and we have nevr had any problems with them breaking or cracking.

They or stackable but they also have a very nice rack that bolts into the van to keep them all organized. The rack lets you get to any bin without having to move others off of it.

Robbie S