IMHO, EVERYONE needs the standard 5 gun battery.
1. A wheel gun. What can't you say about a good ol' fashion revolver? I prefer a .38/.357 but the .44 Special/.44 Magnum works good too.
2. As money allows a mil-spec auto loader is a must. 9mm are cute, but once the hollow points run out your gonna need a real man stopper, and you just can't beat a .45 ACP.
I’d dump your 9mm pistolas and carbine for a good .357 and .45 auto mate.
3. What are your 12s? Pumps, Autos, Break-opens? IMHO the pump action shotgun is a definite must and Remington, Mossberg and Winchester all make affordable 12 gauges. It’s the one gun you can hunt, fish and defend yourself with…LOL!
4. The "black rifle". Some like it, some don't, but most agree that it works well in the 0 to 250 yard range. The AR-15, Mini-14 and AK-47 are all good choices. The AR-15 is pricey and requires ALOT of cleaning. If'n your on a budget and like the .223 (5.56 x 45mm NATO) the Mini-14 is the way to go. But if your not particular, the AK-47 would be my 1st choice. The guns are cheap, the ammo is plentiful; and with the right accessories...
it can hit out to 250-300 yards.
But if your REALLY tight on money, an SKS will do you until you can work your way up.
5. The bolt action rifle. A lot of folks like to combine #4 & #5 together. My first combo was an M-1 Garand in .30-06. Great gun! Still got it and will never give it up. A more modern choice for a 4+5 combo would be an FN/FAL or an M1A (ala M-14). The FN/FAL is cheaper, but the M1A is more accurate. BUT...you just can't beat a bolt action rifle for long range work. I highly recommend a .308 (7.62 x 51mm NATO) for the availability of ammo; and any used gun rack Remington, Winchester or Savage will do you nicely. But don't under estimate the surplus market either. There are plenty of Enfields, Mausers, Moisans, and even the rare Springfield to be had out there. They're cheap, reliable and will do you justice if you know how to "rebuild" them into a modern rifle.