How do you handle or produce receipts as a coin dealer, whether you're buying or selling from the public or from other dealers?
I'm not a dealer, but I've sold to a lot of dealers at coin shows. At shows, most don't provide receipts, or provide them only if asked. Most also deal in cash as much as possible. At the pawn shop I frequent, there's a lot of paperwork for buying, and I assume even more for selling to them. (They want to know how to find you if it turns out the stuff you sold them was hot.)
I noticed the lack of receipts and credit cards at a FUN show. I guess I am paranoid in that if there is no proof that you purchased a coin at a certain price then the capital gain will be enormous. Or do most sales end in under the counter deals? Got to think that at some point Sam will get interested.
I have no idea how those paper-free dealers report their dealings to the IRS. Asking about it would seem rude. (For what it's worth, even before NC abolished the sales tax on coins and bullion, it was rare for dealers at shows to collect it. If you did ask, they'd say it was "included in the price", wink wink. But again, the pawn shop always charged sales tax, because their dealings are heavily scrutinized.)
Dealers have never wanted credit cards at any show I've ever been to. The service fee they have to pay eats into their profit. Cash has always been preferred. However, I have never not been given a receipt at a coin show. It is always hand-written, and has a description of the coin and the price I paid for the coin. I keep all my receipts, hand-written, printed, ebay, heritage, GC, every receipt... it goes into a binder with the coin's ID number (a unique number in my excel spreadsheet). I can provide any receipt I've ever been given.
One has to wonder what would happen to coin shows if the bankers get their way and institute digital currency.
I remember the classified ads in the back of circa-1970 coin magazines, advertising coins for (say) "25c silver" or "35c silver". Mail them a couple of silver coins, they'd mail you back the coin you ordered. I'd expect lots and lots and lots of such bartering at shows if anyone tries to force tracked or intermediated payments to replace cash. Coin collectors and dealers tend to be a... determined bunch.