Storing things like food, medicines, medical supplies, clothes, and toilet paper is basic to long-term survival.
However, IMHO, the most important starting point is the storing of weapons and lots and lots of ammo.
Otherwise, eventually, your stored supplies will be used only by others...not necessarily strangers.
Got any recommendation for someone who has never used a gun and needs to hide it in a small location. My mom was an ace shoot, but I've never had a gun.