At some point in our home remodeling project, we were about to lose our concrete guy due to weather. It was a El Nino year, so of course we were grading and pouring during the winter!
So we got a thought. Instead of losing our concrete guys, maybe we should expand our scope. So we had them grade what was already a pretty flat and unused section of side yard and pour a 20x20 pad. We figured at some point we'd install a greenhouse.