Might modify those four guns to five:
A military caliber service pistol, an easily concealed handgun, pump shotgun with extras, a hunting rifle in military caliber, and an AR or AK type rifle with plenty of magazines & ammo.
Anything additional is pure gravy...and I’ve got plenty of gravy.
;^)
My must have SHTF in survival mode guns are:
.22 cal, Ruger has an excellent one for circa $200. Small game.
AR in 556/223. Can be had for circa $600. Personal defense
12 gauge 3”” or 20 gauge. Obtainable for circa $400. Game and Defense
9MM...$500 will do just fine here. Defense
30-06 or 30-30 or 243 cal... Large game when not expecting Rhinos! Ammo readily available.
Know that ammo more important than number of firearms too unless you plan to use them for clubs.
Any individual who feels he will be holding off an army should forget it as mass and firepower will overcome.