I decided a long time ago that I'd rather have too much (and have some left when I croak) than to wake up some morning, old and feeble, having run out, and wishing I had bought more back when it was cheap and readily available.
Which brings up a point I'd like to make. All my nic in my vape fridge freezer that is bottled in glass it didn't come in is in plastic bags inside el cheapo locking cash boxes with appropriate warning labels saying poisonous nic is inside with strength and date of purchase, the appropriate skull and crossbones, and warning about disposal. These boxes aren't meant to keep anyone out that really wants in, but are in case my wife and I came to an untimely demise.