I first bought one shelving unit to see what I thought. I liked it, and it was straightforward to assemble. I decided to buy three shelving units to put in the loft of my garage. They were 48" wide, 24" deep, 72" high, and they looked fantastic. I then decided to put three 39" x 18" x 72" on opposite sides of the loft. I used half the height.
I added another one downstairs, then two more, and I just bought three more. These are wonderful units. Highly recommened them.
Rich