I have noticed something about gunstores.

[Freightman]

Here is another reason, The city requires you to hold a gun that you bought off the street (walkin) for 20 days while they run the numbers, I cant afford to tie up the money and stand a chance of loseing the money altogether in the case of a stolen gun.

 

[Ed Brunner]

Regardless of how it is explained, a dealer must make a profit. Otherwise he is guilty of philantrophy and the ATF or IRS will censure him.
If he gives you a "fair" price on your trade-in, will he be able to sell it for a profit?
No comparison to the car business. Many people have no idea of the actual price they paid for a car. All they know is that it was something like $487.63 per month for life, tax title and out the door.

Suppose you needed a federal license to sell cars.