Of course, these are just some ideas to give you inspiration.

Under carpets if you have a basement or live on a concrete slab ranch home for instance. Some fires destroy homes completely except for the carpeting. As soon as water is hosed into the fire it all ends up drenching the floor and carpets. Most carpets on concrete floors usually survive with being turned to ashes. Paper documents and money under these are protected from fire damage. No air for the fire and drenched by truckloads of water, your money will be recovered. Just NEVER let ANYONE know about it. Maybe slip a note about it in your important papers so if you die in a car accident for example, your family will have to take time to go through most of your papers and hopefully find your note of your secret savings stash. If there’s 1 person you can trust who doesn’t live with you and go everywhere with you and may not die in the same accident you do, then trust that one person. But no one else. Hopefully it’s the one you want to have the cash after you pass on.

Anything hidden in walls and ceilings and underfloor boards will cook to ashes especially if there’s fire started below, as it always goes up first. Fires, tornados and natural disasters should be considered when making a plan for secure and recoverable assets.