Folks,
A lot depends on when you started and what you accumulated before that cannot be readily gotten now.

As an example: ALS used to sell CS gas and smoke grenades to FFL dealers. They no longer do. Not against the law, just a change of policy. Some folks added CS to their stash when they could.

Not readily seen but fully functional CCTY cameras with a thermal or two outside as well as regular IR PTZ cameras. With night vision you can see the IR cameras at night. Without NV you cannot.
These are not bad in price and highly effective. I have seen the camera's alarm be tripped by a pair of squirrels 60-70 yards away.

Granted, the odds of wandering into a hardened location are slim. But they do exist. I'd surely hate to be scouting a place only to find out they have me on thermal and getting ready to send the welcome wagon out to "greet" me.

There is a lot to be said about recon the tree line with a drifting cloud of CS and advancing with it to see what you find coughing and hacking.

When it starts, you do not want to be grilling steaks on the deck and not expect the un-invited dinner guest to show up!

The power grid will be iffy to say the least. If the grid stays up, most folks will remain somewhat civilized. If the grid goes down and stays down you about 3 to 7 days before most folks get restless. At 7 days to 10 days if the grocery store is not open with food and there is no power things are going to get dicey.

Even inside gensets that exhaust to the outside make noise. Used sparingly 200 gallons of fuel will last quite some time. But you WILL make noise with it. Propane grill tanks, have a lot of them on hand. A camp/canning/cooking burner will give you another source. If you are setup for it, firewood. Always have 2-3 years worth ahead or more.
There are ALOT of armchair warriors on the internet. They can talk the talk, but are they ready to walk the walk?
You are correct about a defensive position being hard to defend. It depends on how hard the owners of the position choose to make it and if they wish to "foul" the earth so to speak. You can snipe at them. But I'd be willing to bet the next time you came back you'd probably have to be on the look out for party favors that have been left at or near the best spots.
If chaos is now the name of the game. A good chainsaw, means with a large bar can restrict road access quite a ways off. Most folks are a tad lazy and do not wish to have to hump it very far.

I fully agree with the above statement: Be such a hardened target that they will seek a less aggressive target to visit that is less likely to have them loose body parts.

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