Id recommend giving your spare set to a trusted relative or mate with a licence because.
When the set you use is taken from your ute or you lose them or whatever and you cant find the set you put in a "safe place" 5 or 6 years ago you have to cut your way in and.
You cark it or are no longer fit and proper at least the person you want to look after/inherit/sell etc can gain access without destroying stuff.
As for hidey spots I am all ears.....totally impractical for me to have my keys on me all the time I would lose them once a week.
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