OK - so I have a "studio" in my house and not in a metal building so I can not answer your question directly. However I would say that it would depend on where you are located. I have seen metal buildings actually finished into a house with regular sheetrock walls, back when I lived in Virginia - came out really cute and very affordable for the family. I am guessing it really depends on where you live. If it is up here in the northern USA - I expect you would want real insulation and sheetrock. Somewhere in the south - you could get away with prefinished interior "paneling", I would think. Does it already have electric? If not - when they ask you how many plugs - go for the maximum number of plugs (use the four outlet type - I regret not doing that) and several circuits. It is amazing how much energy a flat iron and lights consume. Good luck!