There are obvious and tremendous factual differences between selling a single firearm on Ingo and bringing dozens of them to a gun show and renting a table on which to sell them.
I never said that it was illegal to buy a gun and sell it at a profit. But admitting that you do not have a job and that you are selling a gun at a profit at a gun show sure makes the question much easier to answer as to whether you're supporting yourself with income from firearm sales.
There is no specific number of firearms one needs to sell in order to be a dealer. It could be as low as one.
the intent to buy then turn around and sell for profit has to be there in order to make you a dealer.
Just because someone is out of work and selling a gun for profit does not mean he is making a living off of the gun. Many members of the gun community have fallen on hard times once or twice in their lives. They have sold guns to make ends meet, at a profit. This does not make them a dealer as the original intent was to buy the gun for themselves.