The key is to get a perfectly level surface. Took about 12’total hours to complete over 3 days. I made the entire lower half of the greenhouse in our garage and my wife and daughter and I carefully carried it out to the platform for permanent placement on a pressure treated foundation deck. Pay attention to the instructions that advise you not to tighten many of the nuts and bolts until the final stages (so you adjust the geometry as needed). Once complete, go around in a linear fashion and tighten everything. With the final step’s plastic corner braces in place, you’ll be amazed how firm the structure becomes.  There are many helpful videos on YouTube that will explain the process, too.