How long do carts/vapes last long term?

I usually do edibles and get packs of 10 100mg ones. I do about one a week so I know one pack should last me about 10 weeks. How does that compare to a 900mg vape? I've been meaning to switch to them instead but feel like they'll run out a lot quicker

I also want to buy a lot and store them to use long term, is there anything I need to know about storing vapes? I heard people talk about keeping them upright

thanks

i had a 5g cart that lasted me like 5 months of pretty much daily use