I bought this for pretty cheap at an auction and I don’t even know if there are instructions inside. I’m a pretty handy guy with time and tools and some knowledge. I’ve worked on roofs before and know the basics of many other trades.
You might be able to do it by yourself, but it would prob be a lot easier if you have a helping hand when spanning the supports.
It also depends on what you're wanting to do with it. If you're just parking a car or a boat in there I've seen people just use a gravel foundation with concrete footers. But, if you are wanting to make it a functional workspace you may want to pour an actual foundation.