As I write this from my backyard office shed that my dad and I built together. All told we put about $3k in. If you want to do it much cheaper: - A Tuff shed i

As I write this from my backyard office shed that my dad and I built together. All told we put about $3k in. If you want to do it much cheaper: - A Tuff shed is a bit overkill. For a small shed (anything under 8') you should really be pretty comfortable framing it yourself. There's no fancy cuts and it comes together fast. - Concrete foundation is definitely overkill. Unless you're storing a tungsten collection in there, simple post blocks are more than adequate. - Windows and doors! You can save a ton of money by finding secondhand fittings at Habitat for Humanity or Marketplace. You have the benefit of being able to design around what you have. - Forgo drywall altogether on the interior. Wood paneled walls are easier and cheaper (it doesn't hurt that I designed mine around a "British pub" theme. - A split system is WAY overkill for a space like this. Just leave a cutout in the wall to mount a decent window unit heat pump. If you know what you're doing, or have someone to help, you're looking at about 2-3 days of work.