Got the wall panels with openings built, will do the roof tonight.
I'm going to spend some serious time on the doors / windows to try and do a good job with them.
Something I did on my last one that worked out great was a simple 3" to 4" sheet metal "drip awning" right over the top of each window to keep a little less rain and drip from blowing in.
Also typically install a few shelves and coat hooks.
I will be able to pick this whole rig up with the forks on my loader tractor to move it.