Depends on what you are looking for- if you just are looking to stay stocked for short term, thats one thing. If you are talking long term in case of a ban, thats another If short term, then a couple of 30ml bottles in a couple of different strenghs ( 1 higher and 1 what you usually use whould be good ). If you are talking long term, I would recommend some quite high nic juice with some doubler (like Tasty Vapor) so you can mix what you need when you need it. I personally used a small ( 3ml bottle) and tracked how much I used over a period of time to see how much I was actually consuming. I am now trying to buy what I think I might need for the next couple of years in case there is a ban. After trying to research on how long juice is good for, 2 years seems to be the limit for most sources that I have found, so that's what I am going for. I also did the same for hardware, and have tried to buy to last that period of time. I'm also trying to reduce my nic intake over time, so if it becomes hard to get it I can just make my own non-nic juice. Hope none of this is needed, but I'd rather be prepared than not! Happy Vaping!!