Hiding among the treetops reminded me of a house plan I've saved for years. "Build this at the back of the Pville lot," is written across the top. It's in the shape of a barn and appears to have a silo and tractor shed attached. The silo is instead a tower retreat that I thought would be great fun, especially if I could see out but no one outside could see in. Tinted glass should take care of that nicely. I would probably flip this and build the mirror image.