Studios don't really take up much juice, probably less than your fridge. If you are running a huge PA and lights then you might be using up more. If you are talking about a commercial space with HVAC and the whole 9 yards then it will be more costly and could vary greatly depending on your location.
I just purchased some OC 703 rigid fiberglass and it was about $.90 per sq/ft for 1.5" thick. The rest of the cost would depend on what type of construction you are doing. Are you using brick or wood frame and drywall?