To sum it up in a word, yes.
To save money, and more importantly, my sanity (what’s left), I like to first define the problem, then look for the answer.
Where a cache would be useful, in my mind is for a fall back plan.
The first thought I had is if your BOV has to be abandoned.
If you have to bug out from point A, to point B, in a perfect world, it’d be no big deal. You would have everything you need in your BOV, and away you go. But if some unforeseen event causes you to have to abandon you vehicle and continue on foot, a pre-planned cache or two along the way would be nice to have. Even if it were something as simple as a 5 gal bucket some basic stuff. I would keep it simple as to the content, things like dry socks, food, matches, simple water filter, space blanket, a bit of ammo. A few of these along the route might make a huge difference in your outcome.
But what if you could not get to your bug out supplies? House burns down, gets blown away by a storm, chemical spill, what ever.
Having a cache located at trusted friends and/or relatives would be nice.
This could be a rubbermaid tote or one of those plastic lockable job boxes. I’d take this a little farther than the first cache. I’d add some extra cloths, maybe an old but serviceable pair of boots. Food, ammo, cleaning gear, mags, basically, a scaled down version of what you had planned on bringing anyway.
Currently I am working on this idea. I have put together 50 cal cans that contain a mix of 6 loaded AR mags, 4- 120 rd bandoleers of 5.56mm, and 200 rds of 9mm ammunition. The next step is some kind of tote or box to put a change of cloths, foot wear, a brick of 22lr (only because there is no room in my ammo can for it), knife, and what ever else I can think of. Step three will be to put together some long term storage food.
I plan on keeping the total package as small as possible. I also want at least two of these set up, in locations that are in different directions from my house. The idea being if forced to Bug Out, and the event is between me and one location, there is a fall back location in a different direction.
The hard part of doing this is that you must really trust the people who you are leaving your cache with. Just because someone is related to you, does not automatically mean they can be trusted. To prevent them from confiscating your cache during an emergency, they are going to have their own preps. It would go without saying that the ideal way to set this up would be to have a minimum of three people/families involved, to include you. Each forms part of a triangle. Each is welcome to go to the others home as a BO location.
The rental unit idea, in my mind is just taking the 5 gal bucket cache idea and expanding upon it. If I had to bug out from point A to point B, and the distance was interstate, or measured in hundreds of miles, then this is a great idea. I would look for storage units in smaller towns, on the outskirts. Would hate to count on those supplies only to find the riots have burned the building down.
This is where I might add some camping gear, and some treated gas.
I have been kicking these ideas around for a few years.
If using a storage unit, or the cache with relatives and friends, I have even thought of extra firearms. If going this route, then I would personally use guns I bought from a private source, with no paper trail. I would only do this in case the guns were to be stolen. This is where the trust factor really comes in to play. In the storage unit, you can just stash the guns in something that looks “un-gun like”. The storage unit would look like any other storage unit, full of crap, vs. a cache of supplies.
Side note, I recently rented a storage unit for three months while moving out & separating from the wife. Among other things were over 50 labeled 50 cal. cans of ammo. I put these inside of those card board boxes that copy paper comes in (looks like those “banker boxes”) . I wanted anyone walking by while the door might be open to think it looked like a yard sale at a trailer park. I did not want them to see the labeled ammo cans, and think, “Hmm”.
Sorry if I was rather long winded, but I have been thinking about this since about 2004.