Regarding nicotine, not sure if longterm storage has been addressed here yet, but the rule of thumb is that light, heat, and oxygen will degrade your nicotine, eventually making it unusable. So to remove those 3 things, it is advised to freeze your nicotine longterm in glass with minimal headspace, in other words, minimal air in your glass storage container.
I have multiple 30ml glass vials with polycone caps for nicotine that I take out regularly and refreeze. For the rest, I have stored in large glass jars with polycone caps in the freezer. If there is significant airspace in the glass container, I purge it with wine preservation spray, which is basically inert gas that displaces the oxygen. I go further and tape the cap with silicone tape for extra seal and have it locked in a lockbox
One important note I would add. I advise clearly labeling the nicotine wherever it is stored so anyone stumbling upon it will know the dangers it poses. It is a deadly poison, even when diluted to 100mg/ml or even 48mg/ml given a high enough exposure, this includes prolonged skin contact.
So it shouldn't be accessible by children to be sure.