nebby,
E-juice: buy high sell low? No buy high, store in fridge, mix down.
Tobacco: I guess you could study, learn, but reserve actually making your own NIC juice until later, if things got really really bad. No need to poison yourself now

Batteries: I still go with the use it or lose it position. I rotate my batteries. Just hoping one will die, so I can make another MOD

MODS: Even if you don't like them now, make sure you no how to, or at least be able to make one if you had to. Times get hard, you would vape a cartomizer from a couple of solar cells if you had to.
Attys: seems to be the short straw, well maybe next to juice.
These you could probably do the double bag, 10 year cold storage trick.
You're a hands on guy, why don't you try and make a mod?
Drill, hammer, stuff like that. How about one that would run off a 6 volt lantern? and still be a 6 volt lantern. I mean, just in case things got really tough.
You'd get guidance here.
Rocket