Sell guns to other players! GM,s read!

Hello everybody out there !
I dont know if this has been taken up before but then i do it again !
I think that there should be a place in game where you can sell your gun to other players and get more of tehm than you get when resell them !
If u have an m4a1 it costs 43000 and when u resell it u will just get like 14000 ;(Sad); but if there is a way where u can sll your guns to other players maybe you could sell your m4 for like 35000 instead of getting ridiculous 14000 of a gun you bought for 43000 !
If this is goin to happen maybe the players wouldnt complaining about the GP that much !

I hope a GM read this !