most of my gun selling is in the family normally between my dad and others so they are always around, but i have sold an ar and a ruger p95. the reason i sold those were for the simple fact that the ar was an a2 and i wanted an a3 etc, and the ruger was da/sa and i don't like. i also sold a beretta 92fs, i took off the accesories and sold them individually and kept the m6 light, sold the gun and still came out on top.
the only time i have had to sell guns and not want to was right before i went to iraq in 04. because the army for some reason gave me 2 no pay dues, and i had to pay the rent and feed my preganent wife, so i sold my wincehester model 70 in .270 the first rifle i ever owned and one i had had since i was a little boy, a remington 1100 that they no longer make, and armscor ak 22, two guitars a 160watt fender amp, a gibson less paul, an ibanez rg350dx, and my digitech effects board, drum machine and 8 track recorder. hard times are bad but family is a little more important that all that material stuff.