"We hide my extra key in a fake stone. It looks like real. Moreover, it even feels real! There is room for 2 or maybe 3 keys. This fake stone blends into our garden nicely.
My husband insists that we purchased a mini safe like this, but I don't think there is a need for it yet
https://secretstorages.com/wp-content/uploads/2017/04/master-lock-5401d.jpg
If any family member and I lived close by to each other, we each would definitely leave a spare key in the other's meter box. Also I like the idea of Biometric door locks. They are not science fiction anymore. Then you just have to remember to always have your fingers with you
"