Greenhouse frame sketch
The useful plan is the one that survives walking around the site twice.

The first layout put the door on the side that catches weather, which looked tidy on paper and annoying in real life. I moved it around the corner, shortened the ridge, and marked the posts again.

The better version is less dramatic: four cedar posts, a plain gravel pad, and polycarbonate panels that can be replaced without taking half the frame apart.

Measurements

The useful lesson was to stop optimizing the sketch and spend ten minutes standing where the door would actually open.