If you buy from Shed In A Day, I would recommend that you have them assemble it as it will give them an opportunity to correct their mistakes and hide their poor quality. I bought the "kit" and received mis-marked and mis-cut components, a damaged wall and truss as well as two 2" X 6" joist warped more than 1-1/2". Trying to deal with this level of quality insures that, even if you have the proper tools, it is much more than a one day task. When I finally heard back from the owner, he passed them off with being normal in the industry and that my expectations were simply too high for a $1,150 shed. He made no offer whatsoever to correct these issues.
If you do choose to buy the kit, you'll need to have someone fairly strong at home when delivered as one guy is sent to unload many large, heavy pieces and it is clear that damage could occur. In my case, we had to unload and reload walls from another larger shed loaded on the trailer on top of my components in order to get to them. Again, the owner discounted my concern and told me that he doesn't tell me how to run my business.
I would not do business with this company again.