I would never leave a firearm in plain view in an unoccupied vehicle! I'm not sure exactly what the law states regarding such but I believe that concealed carry only applys if the firearm is in the vicinity of your person where you have direct control of it. I may be wrong as I've seen arguments against that statement, so further research to verify that should be taken upon your part. My Jeep has 3 steel locking consoles that I can lock my firearm in if ever needed. My Jeep has soft doors and no locks so the steel boxes are a necessity for protecting against theft of other items. I also have a CCDW so I'm covered by the law either way.
What type of building are you referring to?
1. Gov/State building where OC is banned?
-I rarely ever have to go to any type of facility such as this. The courthouse is about it for me. If I knew that I must venture into one of these places, I would opt to leave my firearm @ home where I knew for certain it would be safe. That does leave you unarmed though during your entire trip to and from. Another option would be to install a decent security safe in your vehicle in order to store it securely. That way even if your vehicle was vandalized, your firearm is still safe and sound.
2. Business with a "No Firearms/Weapons Allowed" sign posted?
-Each business has different views on firearms. Some are completely anti-2A, some post signs b/c of their corp guidelines yet tend to follow local state law, some post signs yet don't care whether you carry or not and then there's the awesome Pro-2A businesses. Whether you see a No-No sign or not (I don't even look for them anymore), go ahead and carry on! Your life is more important than their policies or personal convictions. If they stand their ground on the issue and ask you to disarm or leave, then leave (never disarm unnecessarily). You could also inform them that you won't ever be coming back. I like to add that I will spread the word regarding their Anti-2A stance among friends and family.
Sorry for the long response and I feel like I may have left something out in my answer. Hopefully, if I have, others will chime in as well.
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