Our plan is to have 3 buildings. We want to have one ready to go so we had it delivered pre-built. We got it from Jamaica Cottage Shop (jamaicacottageshop.com). They were super easy to work with, but at times their communication was a bit lacking. After a couple hours it made it to the foundation we built.
We had it built with no windows. Once we figure out our floor plan we'll get some energy efficient windows. We'll have to seal, insulate, electric, and plumbing. Solar, rocket mass wood stove, and tons of other fun adventures.