Oh boy -- I can't wait to watch your progress on this GH, Melissa!!
When I saw the post where you said you were thinking about going with the GrowSpan GH, I had to google to see what it was like... but I forgot to put in the "Pro" part and ended up finding the Gothic HobbyPro, which looks to be a really nice "hoophouse." I'm seriously considering going with that one in the 16x20 size, to replace my aging (and deteriorating) 8x16 Rion GH; my plan would be to orient it in the opposite direction (N to S instead of E to W), so it would cover the same area as the Rion but also extend 12 feet into my veggie garden so I would have the one area still for starting my seedlings and storing my growing stuff, and the larger area for in-ground planting. If you -- or anyone else here -- has any knowledge about the GrowSpan HobbyPro greenhouses, good or bad, I'd love to hear it!