I've never had a problem with anything I've bought on Gunbroker.
I set a top price and I don't go one penny over it.
Don't get into the mindset of "I won" or "I lost".
Sellers only charge sales tax if you live in the seller's state. Read the seller's rules, how he is to be paid, how much for shipping to your FFL, etc. (before you buy)
If I am the high bidder, I e-mail the seller immediately, tell him what I'm going to do (USPS money order, etc.) and then I follow through promptly.
If I am not the high bidder, I start looking for another one. There's always another one around the corner. Don't feel bad, move on.
Gunbroker is expensive, you might want to try Gunsamerica.com
??? There is no charge for the buyer. If you mean a lot of folks bid on Gunbroker, maybe, and why's that? Because they have what you want. Thus, the sellers with the best items will gravitate to Gunbroker.
My LGS, nice folks, small selection, sells a bunch of guns on Gunbroker, so don't feel sorry for your LGS. Plus the LGS gets the $30 for the FFL transfer.
That means that, on average, your out-the-door price will be $50-$80 more than the actual closing price of the auction....
True. But I have always found the extra cost is more than offset by the savings in sales tax, and the high price in the LGS.
I'd also recommend looking at Davidson's through a LGS. They sell new, and are a good gauge of price.