In a "free market", people can still come and bulldoze your house. Who is going to stop them?
You have two choices: you can hire your preferred protection agency directly, and get a discount rate on your homeowners insurance, or your insurance company may have a large-scale deal with one that makes that a better option.
Or you can not buy insurance and protection and go it alone with your shotgun, but that doesn't seem like the wisest of approaches. But if it comes to it, and a conference center developer wants to raze your neighborhood to take your property, at least he won't have a gang with an ultimate claim on violence to use to do it (c.f. /Kelo vs. New London/) and you can try to defend your land if you want to.
Even if he succeeds, that conference center developer is going to get the worst of reputations and likely be excluded from other geographic regions by force.
If you actually care to learn about some of the proposed solutions to a violence-based society, in regards to security, here's an easy way to do it that takes less than an hour:
https://www.youtube.com/watch?...