There are many decent sellers and traders on here and CGN, check the trader ratings for them, and see if you recognize any names.
That way you can PM someone you know and trust if you already do not know the person you wan to do business with.
I have sen several guns come and go over the years in shops that had problems, so instead of fixing them, the guy got rid of them on a trade or whatever.
Without shooting the gun , you could not identify the problem!
Myself, I would not be able to live with myself if I did that, and although I know many others with the same attitude, I also know many that would not hesitate to get rid of a bad gun to a shop.
I don't pass on my problems to others, but it is "buyer beware", for sure!
Cat