I have a 16x24 patio, and the small concrete slab in front of the 6x12 shed. mostly hand tools, few power tools, 2 jacks, 2 jack stands, 8 rims.... and natural heating and cooling (I can adjust the thermostat unfortunately), no shade.
in other words, i work in the back yard.
My Uncle on the other hand has a 2 car garage with 10 or 12 foot ceiling... and climate control.. I have my CJ-5 in his garage with his 300ZX