The Second Amendment means that the government won't infringe on your rights. It doesn't refer to private property and it's your choice whether to go on to the property and abide by the owner's rules or stay off. That seems simple to me.
In fact, I don't see this as a 2nd Amendment issue at all, but as a private property issue.
What if your guest kept his gun in his car? Are you going to go check it to see if there is a gun in it?
What if the gov't favored anti-gun kompanies, and penalized pro-gun companies? Then you'd have the gov't banning guns via 3rd party, which is just as illegal as if they did it themsevles.
Now obviously, you aren't going to find federal statues favoring "anti-gun" over "pro-rights" companies, but federal laws and regulation DO favor larger korporations over smaller ones. And the former tend to be much more anti-gun than the latter.
Turning away people coming IN your house with a firearm with alcohol being served is one thing, but taking your dog OUTSIDE and searching your guests vehicles (THEIR private property) for guns (or anything else) is another. THAT seems simple enough to me for anyone to understand.
You may be right about 2nd amendment rights, but what is your defense for the violation of the 4th amendment? I believe that the Constitution trumps private property rights in this case.
Fourth Amendment - Search and Seizure
"The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized."