@Animats said > A place that just stacks empty containers 2 high probably only has large forklifts. The special equipment for high stacking is far more expensive, and only bought if you need it.[2]

Some facts:

1) Container Height: 8'6". Add approx 4" for the lift slots on the bottom.

2) Forklift with 22' lift available from Sunbelt = 3 Container Height / 50% increase in yard capacity https://www.sunbeltrentals.com/equipment/detail/1044/0550320...

3) Common "construction" type forklift with 39' lift from United Rentals = 4 Container Height / 100% increase in yard capacity. https://www.unitedrentals.com/marketplace/equipment/forklift...

And United has forklifts with even higher reach available.