Safes are usually found inside various locations and outposts. You need either the Repair Torch perk or the Lock Picking perk. If you don't have these perks, you'll have no choice but to use Remote Explosives. However, getting the remote explosives unlocked will take more time compared to simply allotting points to the mentioned perks anyway. Safes contain Titanium, which is a somewhat uncommon resource. They can only be looted once.
Normally safes are hidden in inconspicuous spots like under or behind boarded sheds/houses, inside locked doors, etc. To make it easier to spot them, bring Timber with his second ability unlocked. With your trusty canine companion around, the exact locations of crafting resources and titanium will be revealed and visible even behind walls.
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