On our family farm, this building was called the "bull pen", cause thats where he lived. Big, nasty old Holstien bull. About 15 years ago the roof & sills were shot & I tore it down. Finally got back on track. The two 8x8 posts are locust, they'll sit on layed up cement blocks that go down 40" to the footings. The main beam is spruce, it's 6x12x14 ft long.
I put it together on the ground with 2 braces, squared it & lifted it into place with the small crane on my F350.
Everything was sawn out on my bandmill, 16 ft 2x10 rafters give a nice overhang.
I used one inch thick pine for roof boards rather than buying plywood [cheep I guess]
The last pic. shows the almost finished shed, I should get one more pic tomorrow as now it's got a bunch of firewood under it plus a 4 wheel running gear.