Most collectors concentrate on a theme, a period or some specific firearm. Many specialize on Colt black powder revovlers, or cartridge conversions. Maybe patent evasions of the Rollin White patent. Winchester lever actions, or military arms.
I haven't really thought about it this way.
Do I want a particular "theme"? I guess not. I know some who own multiple variations of the same gun; different years/barrel lengths/nickel/stainless/blued/etc. I'm not really into having multiple variations of the same basic weapon...I'd rather have multiple weapons that are completely different. I would like to accumulate at least one weapon in each common cartridge:
9mm (have it)
.357 Magnum (have it)
Ideally I'd like iconic in the sense of cultural icons. Everyone knows the .44 Mag as the "Dirty Harry gun", everyone knows what a .38 Snubnosed revolver is, everyone knows what a 1911 .45 is, etc etc.
Right now, my budget is mainly in the hundreds of dollars, not thousands. EVENTUALLY, I'd LOVE
to have an 1873 Colt Peacemaker and a German WWII Luger P08. These two would really be necessary, in my eyes, to complete any true collection.
Rifles? I like rifles but for now, I'd rather concentrate on accumulating a nice handgun collection before I delve into the old Winchester rifles, AK47's, and Tommy Guns.