I did not even bother to read the umpteen other responses. I will tell you without any hesitation or doubt: The best kind is built by a local (nearby to you) company that will erect it completely in about 2 to at most 3 days. They will do it FAR better than you can and it will both look great and be durable for many years. These companies have become an absolute marvel to me in the last couple of decades -- quick, efficient, and high quality end results. Use prefinished baked finish steel. The roofing type that is custom cut to length and is NOT pieced to make your longest sloped roof dimension. Typically the entire materials list is delivered on a trailer truck. You prep the site, get it level, do the ditching, etc. They erect the building.
It depends of course on widely varying needs, pocketbooks and wants but I strongly say have a concrete floor put in it. I was foolish and did not do that and sure wish I had.
It is up to you but the best buy in my opinion is prefinished steel all around (sides, roof) using 4x6 verticals. You decide whether you want insulation, skylight translucent panels (you will want several) , how many doors & windows, ventilation to prevent sweating, etc. You can get the specs on the basic building from the installing company and then beef it up or make changes you want. Like closer spacing of sheathing boards under the roof, heavier trusses if you think you need them, etc.
Other items of experience: Bigger is better than what ever you were planning, guaranteed. Taller is almost as certain to be better also. It cannot be built too big.
View attachment 738144