The urban sprawl will be filled with more resources than the wilderness. It will be filled with more threats and more people looking for those resources. That doesn’t make it easy. Still, you could have a situation where things are going to work out in your favor if you have cached resources in smart places. When you think survival cache you may think of something buried. You can hide preps anywhere and post collapse you should move them often if they aren’t buried.
This article offers up 6 thoughtful places for hiding things in an urban scenario. One of the keys to any survivalists success is being a master of their environment. Just as a naturalist is versed in the trees and bushes you must be a master of the dry wall and the construction.