When I was in college, I had this summer job every year, working for the city's rec and parks division. It was a low-cost daycamp program offered to neighborhood families who couldn't afford professional daycare.
Now, I was assigned to work at a location called Princeton Park, which was literally less than five minutes from my house. The park grounds were several dozen acres of relatively open space with a broad, tall hill in the very center. Atop this hill was the building itself.
This place had been built in the 50s or 60s and had been designated, at one point in time, as an emergency shelter. It was composed out of brick and concrete and steel. The doors were made out of steel. The windows (what few there were) were reinforced because it is in a fairly shitty neighborhood.
One of the first things I noticed when I walked into the main lobby the first time is how everything can be seen from one central location, behind a heavy wooden front counter. If, for example, a person had a mind for violence and a mean to impose it, he could set up shop at that desk and have a clear line of fire to each of the three doors.
This main lobby adjoins a long hallway which runs down to a steel door that opens onto a partially fenced in parking area/loading dock. There are rooms that run off of that main hallway, but basically, it's a straight shoot from the front desk to the end of the corridor.
On top of that, there is a steel gate that rolls down from the ceiling, that can be used to close the lobby off from the hallway. People cannot get through it, but bullets can.
Right off the lobby is a kitchen. Never knew why there was a kitchen, but it's stocked. Beside that is a small auditorium large enough to hold nearly a hundred people.
There's a pool area which does open through a sliding door outside, but the are is walled off outside by a tall chain link fence. Also to discourage or outright confound local trespassers. The pool has a massive water filtration system and an entrance to a rather spooky basement. Once or twice, I had to go down to the basement to grab stuff or put shit away, and I noticed a generator down there and a fuckton of more supplies.
Water filtration and a gennie. Hmm. My second week working there, I had already realized some serious muthafuckas had designed this place.
Now, because I am Strict, and I think about crazy shit all day long, I soon realized how bad-ass this place would be if there was a zombie apocalypse. The exterior grounds provide a perfect "killing field". There are only just a few trees here and there, and from the top of the hill, you can shoot anyone or anything setting foot on the property. There is almost zero cover.
Of course, zombies don't give a shit about cover, but looters and mutant bike gangs seeking Go-Juice do.
From the building itself, a small number of armed defenders could hold off a much larger force. There are these low rising brick walls by the front and side door that provide limited cover for firing positions. And if need be, the defenders can easily fall back into the building from those positions and bottle up behind steel doors.
Should the place be breached somehow, defenders can hold the main hallway from the rooms that open off of it. These rooms are all interconnected, so defenders can fall back to the main lobby if necessary. And from that lobby, you can hold the entire room from that massive desk. And when I say that desk was massive and heavy, I'm not fucking around. It was solidly built.
And the beauty of this whole layout is that even from the hold-out position at the front desk, you can still abandon the place if need be and completely bounce.
This place has a solid, but simultaneously "collapsible" defense system. This is important, because there is no structure during the zombie apocalypse that you should not be willing (and able) to abandon should the need arise. Most of the people who survive the initial chaos make the mistake of turtling up in a place they can't fall back from. A "last stand" type of place.
Well, that's a defeatist mindset, ain't it? In order to "win" you've got to be flexible enough to jet, because surviving is the only real goal.
On top of that, I got guns. I got ammo. Most of you get tired of hearing about how I love stabbing fools and whatever. My dad was a collector of bladed weapons; knives, swords, even that weird choppity thing you catch a glimpse of in the opening credits of Buffy (that's an African weapon frequently referred to as a "hunga-munga". Look it up). I gots blades, sure. He was also literally a card carrying member of the NRA. When he passed on, I inherited more guns than most humans would know what to do with.
So, you can generally assume that when I talk about having access to the necessary weapons, I'm talking about having actual access to the necessary weapons.
I got a 4W drive vehicle, and I've got a solid working knowledge of the back roads in my town. Fuel and ammo will be the only limitations as far as gear.
The only problem I can see is getting into Princeton as soon as the shit jumps off. It's always open, except on Sundays, but some fuckface might have the same idea and get there before me.
But I digress. As usual. Point is, I'm one of the few fuckers on this entire board who honestly has realistic options beyond getting eaten immediately. You apply this same basic philosophy to your own situations; find a place that has a solid structure and "collapsible" lines of defense, and you'll be well on your way to having a functional plan.
No plan is foolproof. And there will be a lot of fools who goddamn survive. Even my plan is really just a starting point, because fuel and ammo and foodstuffs will run out eventually. But if you've got a tactically flexible mindset, your "realistically" and "honestly" will also include "survival."
"You must be proud, bold, pleasant, resolute,
And now and then stab, as occasion serves."
Edward II: Act 2 Scene 1, by Christopher Marlowe