The PG/VG does not need to be frozen, just store in a cool dark place.
I keep one 30ml bottle of 100mg nic in a cabinet, at room temp. I use a different storage method than many here. Some people might store all their nic in 30ml bottles, for example, such that one liter requires 33 bottles. When they need more nic they remove one 30ml bottle from the freezer and keep it at room temp. It is considered counterproductive to constantly chill and then rewarm the working bottle because of moisture issues.
I do something like this for a liter:
1 - 500ml bottle
1 - 250ml bottle
8-9 30ml bottles
When the 30ml bottles are empty, then I break the 250ml bottle into the 30ml bottles. When that is empty, the 500ml bottle is broken into the 250ml and the 30ml bottles. I might have a 120ml bottle and 4x30ml bottles instead of 8-9 30ml bottles. This means that a portion of nic might be warmed up and redistributed a few times in it's life, but that might be over a several to 7 year period and I don't think it will hurt the nic. I might store additional liters in one liter glass bottles because I know it will be many years before I need them, and when I do I just distribute as above.
All the nic should be stored in amber or cobalt blue glass bottles, preferably with polycone caps (much tighter than basic plastic caps).