I currently had the same concern as I am in the process of increasing the size of my set up dramatically. Use welded wire on the bottom. You know the square pattern stuff that looks like horse panel but is actually much thinner. Its like 60 bucks for a hundred feet. I wanted the same thing, a walk in run. I am using 4x4 posts, that part is expensive. Then gonna use the welded wire on the bottom of it for extra strength against dogs, coyotes etc.. then use the cheap hexagonal poultry netting for the next row and also on the cover. That hardware cloth is crazy priced. This route saved me a fortune. Also after you set up the dog kennel, bury hardware cloth or something similar, not poultry netting cause it will rust away too fast a foot deep all the way around it.