You don't need to have the items but you do need to have the material and skills to make these defensive items. Current laws that are valid now, will not be enforced in a WROL situation. That is when the items need to be manufactured and installed.
Natural barriers (thorn brush, cactus, etc, ) should be already growing, to help channel folks to where you want them and away from where you don't want them. Humans tend to take the least path of resistance, even in SHTF events.
You should know your terrain / property. You need to know the access points and the distance to object in your possible line of fire. With many ammo types, a 50 yard miscalculation in distance, can dramatically affect bullet drop. Example: Zeroed at 200 yards --- 556 drop at 300 yard = 7.3 inches --- at 400 yards the drop it is 23 inches. A miscalculation of 50 yard could mean a difference of 7 or 8 inches of drop, enough to miss your target. Know at what distances you are most likely to be shooting. Mark areas of approach and the distance to various points of concealment / cover.
Now for the really bad news. almost all farms, ranches and homes are not defend-able. Just about ever home has access points on most sides. Approach paths then cannot be watched from within the home buildings. Early warning and information is the key to protecting the home front. Trip wires (smoke signals) will provide intrusion alert but not the number of intruders. It is important to know if it is a couple of folks or is it 20 people, headed your way. Very small group and you maybe able to defend, large group, and you will need to rabbit out. Never get into a firefight if you can help it. All opponents have one major point of weakness, LOGISTICS. Don't attack the intruders, destroy their supplies.
Unless you are a millionaire, ballistic walls are cost prohibitive. Solid 6 to 8 inch concrete can be penetrated by multiple rounds of 308. Now granted that is a heck of a lot better than a stucco wall, but it is still not bullet proof. A concrete block planter poured with concrete and filled with dirt, will stop most rounds, even with repeated hits in the same spot. Thinking out of the box with defenses will go a long way. A planter close in (your protective barrier) and a planter mid point in the yard is a trap for intruders. Once again human nature, intruders see the planter as cover to attack from, you install the appropriate surprises at the planter. Out of the box thinking, verses brute fire power.
As the world turns and the situations get closer to a major SHTF event, you can start burying caches in spots near your BOL or homes. Surprise SHTF event (EMP. Solar) will still provide you with time to hide needed supplies (if you have already picked and prepped the spot). You don't want to be trying to figure out where to bury stuff, while you are still trying to figure out what happen.
The object is not to out fight your opponents, the object is to out live them.
