I have personally known five different New England gunshow dealers, for over the past 25 years (before then, I was unconsious), and they all differ in their pricing policies - just as do their personalities.
Each pricing policy, however, is based upon their "costs", beit simply the cost of ontaining whatever to resell, or including the costs of doing business to attend a show, like table rental, meals, fuel, lodging, etc.
One dealer just does shows, has never had a brick/mortar store, doesn't frequent the web, and usually has a 35% markup on firearms, 50% on direct firearm accessories, and 25% on shooting/hunting accessories.
Two dealers have both brick/mortar stores, and both have websites - and both sell firearms only, initially priced at a $100% markup.
The last two dealers also have brick/mortar stores, one sells only firearms, and both have a 75% markup on firearms.
I like gunshows, because I USE them - as a venue for selling selected firearms, usually to various gunshow FFL's, and sometimes to another private party (always careful to transfer any sale through an FFL), that I would otherwise find difficult to sell by other means.
I've always bought my guns inexpensively, and so have been always able to at least double or triple (sometimes more) my $$$, even by selling to a gunshow dealer, who must then get their "bite of the apple".
A gunshow isn't a panacea, though, since (like anything else) different firearms are popular/not in different markets/areas of the USA.
I only buy a firearm at a gunshow, when I spot, and/or can haggle for, a bargain ( I do DO my homework).
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