LOL, Zombies can't read though. "Protected by Smith & Wesson" means nothing to zeds xD. Neither does the "My neighbor is an anti-gun socialist but residents at this home practice their second amendment rights" Sign ;)
You are right though. if it's idiot proof it is zed proof..
If you are lucky enough to have a second story that you can make inaccessible with barricades or destroying the stairs, don't forget to cover your upper story windows with blankets, tarps, etc. so any light (flashlights, candles, cooking) won't bleed outside. Not only can it attract zeds, it may also attract other less scrupulous survivors that want to take what you have.
I'd board up the windows, brace up the door, reinforce the garage door, stuff like that.
I'd probably put up trenches and barbed wire fences to keep both looters and zombies out, the barbed wire can also trap zombies so I can shoot them easy.
Then I'd go a bit further with more barriers- walls to block off my street from the rest of the community, remotely triggered directional landmines placed strategically, these would explode and slice off zombie legs easily. evnetually permanently brick up the ground floor windows and doors.
You dont want their legs gone!! Then they crawl along the ground and i dont know about you but i would rather have a full size 6 foot target then a low crawler that you cant see till the bite your ankles.
I live in the high desert in a mobile home, so there is no way to zombie proof it as a huge horde would just crush it regardless of how I reinforced doors, windows, etc. No upstairs either. So, my zombie proofing would be making sure my Jeep is 100% 100% of the time.
The only alternative if I wanted to "stay" would be bringing in a steel shipping container. Stock it, drill a couple of air holes at each wall, get in it and weld is shut & reinforce that end with a double weld. The Z's might be able to roll it around, but I doubt they'd be able to open it. The question would be, would it make more sense to just drop it underground, hook up a water line, a septic line and power line from the MH and using like a bomb shelter? All the lines are already buried, so it would just be T-ing off a new line.
Shoot, now ya got me thinking seriously about doing this !