Working on that greenhouse.
Cutting 4x4s to lock together to use as my footer now. Getting a good sense of my elevation changes (Significant). Looks like I'm goign to have to teach myself how to mix mortar and set CMUs (contrete masorny units, or "cinder blocks" colloquially), then fill with concrete. After first digging a trench to serve as a footer, of course. In better news, it will keep the shallower grasses and blackberries from sending roots under the walls and into the greenhouse. May have to lay a french drain around the outside, as well.
Oh, and my wife wants to run water into it now, a sink, and a gardening shelf - so she can pot/repot plants inside w/o needing to run back and forth. So I'll also need to plumb a drain. Not bad ideas, but definitely setting back the timeline some.