Any issue with bring up comps when buying or selling a card?

[Exhibitman]

It's better to do your homework before you engage. Look up the card first, then start haggling. As a seller, if I see someone buried in his phone my concern is that he doesn't know whether the comps are truly comparable because it is so hit and miss, and that he won't really look at the card or listen to me. In other words, it can come off as rude.

For a card that transacts a lot, like a Goudey Ruth, it is relatively easy to get comps before you even get to the show. If a card is in the general range of the comps, I prefer to ask the seller what is the lowest price he will take for it, in cash. You may be pleasantly surprised. I don't generally bring up comps. Just doesn't sit right with me. A seller with a stupid high price won't be impressed anyway.

Rarity is a real problem. If you are seeing comps from 2 or more years ago but nothing recent, there is no real benefit to it, you just have to wing it. My usual response as a seller when that happens is to invite the buyer to go find it for that price and wish him good luck.