I went with plywood turned lengthwise for the bottom 4 feet, then a row of pegboard for 4 feet, then luan for the top foot. I have an "enclosed carport" type with 9 foot walls.
I just finished having the same building installed in central Florida. My plan is to go with rigid foam board that is covered in a metal skin from lowes. I'll use metal studs in front of this and cover with 1/4" plywood from the ground up to 4' then pegboard above to the roofline. The studs...