I have thought about this recently, though I don't live in an appartment. I'm thinking, in theory, the appts. would be considered private property, therefore the owners of said property could kick someone out who has a gun there... Then again, you've got the right to protect yourself in your place of dwelling right?
I've also thought about the point that "what if the neighbors see my gun and try to rob my place when I'm gone?". This is something to seriously consider. I have the same worry, since my carry gun isn't my only gun. I actually have a new M4 rifle being delivered in a couple days. I paid a LOT of money for this new rifle and realy don't want anyone to break in and get it when I'm gone, just because they see me with my sidearm. I'm not in the same situation as you (appartment), but it's still a consideration.
Maybe, if you're going out carrying, you should conceal until you're away from your appts. That is unless you don't have a CPL...
Just a few thoughts, hope this is helpful.