Stand inside the structure and look up... if you see places where light comes through that can be patched... Old screw holes or rust rot.
Since you have to move it then this will be a perfect time to analyze how much rust you have going and You may need to replace one or two of the posts. But seriously just a good pressure wash some dinging out of sharp edges and it would be a wonderful art piece/coop/run.
invest in some rust inhibitor paint or coating.... There are some good ones that covert rust to a material that can be painted over.
Since you live in Minnesota I would go with hardware cloth all the way up.... Mink and weasesls are an issue.... Stoats as well. Stoats can get through an opening under an inch in diameter. They are in the weasel family if I am not mistaken.
for digging predators you can put an apron around the base of the structure. Foxes and Dogs come to mind.... Coyotes as well. I would also add a ring of hot wire around the base....
I am in the desert so I have Bob Cat, Mountain Lion, Coyotes, Raccoons, Weasels, Feral Dogs, I know there are foxes in the desert but I never have seen one. I have lost three whole flocks over the past twenty years. I have been without poultry for about four years now. I need to rebuild, I will be fortifying my next structures.
deb