We were asked to provide some additional picture of our cost effective greenhouse. We didn't want to bury the windows in the ground so we supported the window with railroad ties. The railroad ties on the bottom to make it easier to level and this helped with making the raised beds inside.
Based on the length of the top we were able to add a hinged window on top so we can vent it during hot/warm days. The ends also are removable which also helps with venting during the summer.
This year we planted mainly cold weather plants which we love in salad: lettuce, spinach, kale, broccoli, cabbage, chinese cabbage, tomatoes, parsley and basil.!
The other side of the greenhouse (currently it is an open air greenhouse :)) have fall onions and garlic. We will try to post and update after they get growing.()
If you need further clarification on the design please ask and we will do our best to help. While it took us 2 times to build it we are happy with this one and the life we expect to get from glass not plastic!