Not a response to anything in particular, but a couple of observations about the topic generally:
1) There are three kinds of leasehold interests, and only "a term for years" is an interest in real property. That's a lease in which the landlord conveys the property for one or more terms measured in years (as opposed to months, weeks, or days). So if the lease says, "twelve months", that's a period tenancy, but if it says, "one year", that's a term for years. Because everything other than a term for years conveys an interest in personal property, not real property, the landlord is pretty much in charge - the personal property interest conveyed is a contractual interest, i.e., the lease itself, rather than the real estate. So most commercial rental projects, if not all, are careful to spell out the term of the lease in months. That means that the lease controls everything, and they generally say things like, "we can make up any regulations we want to at any time with or without notice to you, and you have to abide by them". And the only general limitation is that the regulations cannot interfere with the tenant's right to "quiet enjoyment" of the leasehold interest.
2) HOWEVER, most such places are subject to the Virginia Residential Landlord and Tenant Act. And there is a provision in the act that covers the situation we're talking about:
§ 55-248.9. Prohibited provisions in rental agreements.
A. A rental agreement shall not contain provisions that the tenant:
...
6. Agrees as a condition of tenancy in public housing to a prohibition or restriction of any lawful possession of a firearm within individual dwelling units unless required by federal law or regulation; or ...
So they can tell you that you cannot have alcoholic beverages in your apartment, but they cannot restrict your right to be in possession of a firearm "within individual dwelling units" on the property, and that includes reasonable access to the apartments. But "common areas" is a diffent kettle of fish, and someone has apparently figured that out. So my opinion is that if they have a regulation that says "no firearms in common areas", that means those common areas that have nothing to do with your ability to get to your apartment, but it's otherwise effective if the regulation is legally part of the lease contract.