you can always insulate the shed

, when I built mine (colourbond steel) I used Aircell across the roof and down the sides, never had a condensation problem, not toooooooo cold in winter (down to zero - 2 outside), still gets a bit warm in summer (up to 35-38 deg outside), but its tolerable...
probably best to build with a higher roof than you really need if you can, for summer, I learnt that later with a friend's shed...