What I can't get over is the guy who buys a knife or gun THEN asks if he got a good deal. My response is usually along the lines of, "Does it matter now? You already bought it."
Unfortunately, sometimes people go into situations with logic that states, "this HAS to be a good deal, even though I don't have a good comparison" and it often winds up not being such a good deal as thought (sometimes in fact a terrible deal). There are sellers at gun shows who do sell knives for ridiculous prices. I once saw a standard 440C Griptilian for about $250...and it was used. But it had a neon pink sticker on it that said something like "wont last long!"
With smartphones, these situations are easier to avoid. And as noted in my last post, I certainly advise at least attempting to pay less than the listed price as shows as such given one can often find some sort of discount beyond face pricing...especially when paying cash.