Designed and built them (2). With the help of friends. probabaly good plans on the inter net webs. First good ventilation is a must, without it, the mold ( on the panels) will be even worse. cheesy poly carb or whatever you choose. Will fly off like a kite in a decent wind storm. The harbor freight type ones are a joke. Unless you beef the frames, replace the crap panels. But for the very cheap price you get the basics. I would strongly recomend beefing up these things with cross bracing. Also get a power washer because every spring you will have plenty to clean. We used raised beds and installed a watering sysytem. Once that is done, and using heirloom seeds the whole project is worth it. No more Monsanto crapola.