Over the years I've learn to keep a secret key on all my vehicles. I travel a lot. One of my fears has always been that I'd lose my vehicle keys at the worse possible time -a thousand miles from home, way out in the woods, or have them stolen. With a secret key, at least I'll always be able to get into my vehicle.
Years ago, it was popular to hide keys in little metal boxes with a magnet on the back. The key would then be stuck to an inner fender or under a bumper. There are two problems with those little boxes. Today, most cars have more plastic than metal on them. Few good places to stick a magnet. The second problem is that those little magnets wouldn't hold. A few hard bumps and the backup key was soon lost. Rarely was the key still there when needed.
I've a great secret place to hide my keys . . . and you won't find out exactly where. I used to keep a key in the hollow tube of my roof racks. The key fit snugly in the tube. Once in, the end cap was pressed back on the crossbar, hiding the key. It took pliers and/or a flat head screwdriver to to get the key out.
That's the key to a good hiding place. Make it a big difficult to get at. My cousin used to keep a key screwed to the inside of a fender well. He also kept a screwdriver hidden in his truck's bumper. Using only his fingers, he could remove the rubber trim hiding the small screwdriver. Once he had that, he could unscrew the key from the inner fender. He didn't think his screwdriver hiding place was secure enough to hide his key.
It seems like a foolish and elaborate scheme, but I saw it work. He had his truck parked down the river where he planned to pull out from a long river paddle. The poor guy capsized his kayak and lost his keys to the bottom of the river. When he finally made it to his truck, wet and cold, he soon was inside and running the heater. Sure beat a long cold walk back out.
I keep my spare key in a place that can be accessed with the multi-tool I always carry. Should I lose my multi-tool, there are substitutes that would eventually work. A part from the truck is actually removed to reveal the key. Once, while in rural Florida, I locked both my keys and my wife's keys in the cab. Fifteen minutes later, I was unlocking the truck's door.
Just had my truck towed 100 miles away to a transmission shop. Somehow, the tow truck guy lost the keys. The garage called me up and told me they couldn't get in the truck. I told the guy over the phone where my hidden key was. He paused for a moment, then said: that's a really good idea. The key was found and the truck was taken care of.