But if you hide it high enough, how will your kids get in when they forget their key?
My point is that kids will forget their key, use the hidden one, then instantly forget to put the hidden one away, and keep it for their own use. And of course since they forgot to put it back, they’ll also forget to tell you they used it. So you’ll have no idea it’s been missing for a year or more until you go to use it and it’s not there. Surprise, Surprise!
Ah, I get it now. Yeah, my kids are both under ten, so they’re not yet hunting for their own keys to get in, as they’re still supervised, more or less.
I assumed you meant because all their friends are going to know exactly where the key is.
It’s a 3rd-story apartments, there are bars on all the windows, and the front (and only) door is made of steel and has a multipoint lock. I’m not getting in without a professional, heavy construction equipment, or a shape charge.
Heh. I don’t lock that either. It’s a soft top Wrangler, so anyone can unlock the Velcro or cut their way in.
I’m a good, careful driver, but I still wear a seatbelt.
I don’t have a lot of crime where I live, but I still lock my apartment.
I think I could lift the hasps on one of my windows with a bicycle spoke with a bit of damage to the weatherstrip. I don’t think I could get through the window even with a ladder (bad back and a few other handicaps). Probably I would call my grandson who could easily climb through, but he has a spare-key, so that wouldn’t be necessary. Since I have to use a key to lock my door I probably won’t lock myself out anyway.
Could you break into your house?
My cats have the house well fortified and booby-trapped, so no. Any attempt would result in carnage.
Interestingly, when I was a kid, our cat was responsible for getting my family and me into our locked house, after we arrived home without a key.
After a number of failed attempts by my Dad and brother to gain entry, I went around back to the sliding glass door, where the door was secured closed with a stick of wood jammed in the door track.
I got a twig and began brushing it against the glass door, near the stick. Tibby (the feline Tibby, not yours truly) batted at it, as cats do. After a few attempts, Mr. Tibbs dislodged the stick from the track on his down-stroke. He was the hero of the day. 
I live across the street from an elementary school, which is visible during the day. Since I have a locked gate to the backyard, anyone breaking in would have to be in front of the house, and there are a lot of houses in our neighborhood a lot less visible. If I had to break in I could do it from the backyard, and I wouldn’t worry about being caught.
Someone walking in the front door is another matter.
While outside the truck one day, my Border Collie was hopping around the inside and managed to hit the door lock button. We were all locked outside while he watched us with his goofy grin and slobbered on all the windows. Eventually I got the idea to get him excited and jumping at the driver’s door. His continued pawing managed to randomly strike the unlock button and all was well. He had no idea why he had suddenly become such a “Good Dog!” but was reveling in it.
Slightly off topic for the thread, but as a result of this I now keep a hidden key on my truck. A simple door lock key (no ignition) is pushed deep into some insulation above one of the fender wells, and securely taped into place. Once I retrieve this and get inside, I can raise the back seat and use the wrench stored there to remove a few bolts, which allow raising a section of carpet. Under that is a well-wrapped spare fob in a faraday container. I can open and start my truck without having any keys – a good idea considering how often I’m in the woods and lakes. It would be easy to submerge my normal pocket fob and be stranded.
I know how to get in, yeah. The garage door can be defeated without damaging it, and the door between garage and house can be unlocked without a key if you know how.
In kayaking circles it is very common for people to reach their take-out point only to realize their takeout car is right where they left it, but their keys are at the put-in spot in the car that’s there.
Our garage door has a keypad, so we could use that to get into the place even without a key if we needed to - though if the power was out, we’d be out of luck.
The door from the garage to the house locks; we don’t usually bother, but we have a key hidden in the garage should that ever be necessary. My son once forgot about that; he got into the garage quite late (after midnight), and I heard the garage door open, but he never came inside. I finally opened the door and let him in. Dunno how long he’d have stayed in the garage before trying to get our attention.
As far as actually breaking in: We could certainly get in by breaking one of the ground floor windows. As noted, it would be quite expensive.
Hah - that reminds me: on TWO separate occasions, in two different buildings, we got into our apartment by dint of a neighbor going up into the attic space above their unit, crossing over to above ours, and using the trapdoor to get down into our unit. There was no barrier between the attic spaces (which were not usable for storage).
The first time, I was in college. The front door lock malfunctioned and the door would not open. The back door was chained. We called the landlord - since this was, after all, a defect in the building - and while we were waiting, the neighbor’s boyfriend suggested the attic approach.
Which was a huge relief - as the apartment did not allow pets, and our cat was sitting in the front window, watching all the goings-on. We’d have been BUSTED.
The next place was about a year or so later. I was in a townhouse in another city. I walked out the front door, and absentmindedly pulled the door shut - forgetting it was locked and I did not have my key. Again, a neighbor got in through the attic.
Not terribly secure - and quite possibly not up to fire code. But it saved me, twice.
I’ve reinforced the door frames so they should be immune to simple prying and shoving attempts, and the windows all have latches and additional sliding security pegs so in theory they should be able to withstand anything short of smashing.
The main weakness would be the patio slider if it was open - back when I had a dog, I put a stopper on it so the door could be reasonably secure but open enough for the dog to come and go, but not enough for a person. If someone knew where the stopper was and had a means to remove it, they could get in.
Another possibility would be for someone tiny to pop out a crawlspace vent to get under the house. Then they could try to find out where the access hatch is and come in via a closet. With no landmarks underneath, they’d have to do a lot of rolling around through the dirt, rocks, and spiders (EEEEWW!) to find said hatch and hope nothing heavy is on top of it. If someone’s willing to do that, I’ll give them my TV!
When I first lived in Japan I lived in a few old places which could not be really secured so I usually didn’t lock them.
We’ve moved back to Japan into an apartment building on the first floor with sliding glass doors out the to the veranda (which doesn’t have access out onto the parking lot and windows in other rooms.
Worst case would be breaking one of the windows.
When I was in grad school (same place as I mentioned before) I came home from Christmas break to a very cold house. That’s when I realized I didn’t have a thermostat in my apartment, there was one for the entire house and they guy who lived in the other first floor apartment had turned it down then left. (The landlord paid for the heat, so this worked, but he probably never realized that his thermostat controlled the whole house.) I eventually went into the basement and up the stairs to the door to his apartment. The hinges were accessible so I took them off with my handy screwdriver, turned up the heat, then reset the door. If he ever noticed that the heat was up I never heard about it.
Hah!
At least in our cases, no tools were required to sort things out.
I worked doing data entry one summer, in a building that also housed a beauty school. They had to crank their A/C to avoid roasting themselves with the heat from the hair dryers etc… but the thermostat, like yours, was for the whole building. My fingers were nearly blue some days.
I read this and first thought was wow he’s getting to be just like the rest of us, lax on the security. 
Then I kept reading it’s quite extraordinary the lengths you go to safeguarding your house and possessions.
What gives? Border town? Mafia wife, el Chapo mole? If you tell me will you have to kill me? 
Nah, just bore you to death.
A chance encounter with very violent parolee. Upset because I cooperated with police, he promised to return to my house and finish what he started. Found out he was originally imprisoned for a violent, revenge-fueled, home invasion – so I assumed he was serious.
Of course he was released again.
It seemed safer to strengthen the doors and windows rather than 24/7 armed vigilance or depending on a security service. Simple, reliable, and gives plenty of time to summon authorities if there’s a next time. Added bonus that the house is almost impenetrable (compared to most) while we’re on trips.