I think it all depends on the demand for the particular knife you're selling. Most of the buyers on here aren't looking for a BM ascent, or other lower end knives. On the other hand, high demand knives go for next to retail.
Basically, I think its all about knowing the actual value of the knife (e.g. the cheapest you could get it for retail from a reliable dealer.) When people sell their knives used for $20 more than retail, it's because they probably paid $40-50 more than retail, and they think it's a good deal at $20 above retail ($20-30 discount for a LNIB knife).
That being said, I'd like to make the argument that there is NOTHING wrong with haggling. Don't be offended by a lowball offer - it's nothing personal, just business. You have to bear in mind a couple things:
1) The condition of the knife is always in question - I've bought supposed NIB knives on here that have clearly been handled a lot and probably carried: also, NIB or LNIB can have a huge amount of variance. Same with "used only once" - there's a big difference between used once to open a letter and used once to remove industrial carpet from an office building. Even with photo's - you have no idea in what condition the knife will arrive. "Condition" is very subjective.
2) You could get ripped off. It happens. I try to only deal with people who have posted more than a hundred times. Most the people on here are honest - some are not. Furthermore, they may rip you off and not realize that they're doing so: bad descriptions, etc. There is NO protection on the For Sale forums for buyers - at least on ebay, you have some ability to protect yourself and find out the reputation of the seller before you buy. Here, it's much more difficult.
3) Sellers who expect to get 95% of they're money back on a knife are usually in fantasy land. Second hand knives are worth less. As soon as you buy that knife from the dealer, it's no longer worth what you paid for it. With a dealer, you usually can return the knife if defective. Also, the waranty policy from the manufacturers is in place. Second hand knives usually have no waranty.
Low ball offers are the first attempt at haggling. If a knife is worth $100 and posted at $130, and I start with a "how about $35," what I'm really saying is - your price is too high - how low are you willing to go? You should respond with something like "$130 is my final price." or "I can't go lower than $115." I might respond "$115? I've seen it retail for $110 at
www.someknifedealer.com! How bout $100, then?" - you work together to find a reasonable middle ground, or stop wasting each other's time. Taking it as a slap in the face is letting your emotions control your life.
A benchmade 820 AFCK? If its an 820, it's an old style ascent, not an AFCK. 1sks.com has the 820's for $41. The photon microlight II is available from 1sks.com for $15 each (it might be cheaper elsewhere) Looking at it this way: 3 x $15 = $45 for a $41 knife. Seems like an ok deal to me, if the 820 was NIB. If it's an AFCK - newgraham.com has the 800 for $67.50. $45 still seems like a reasonable offer, especially since the knife couldn't be returned and is in unknown condition. Maybe next time, you should make a counter offer - like, "how about 4 microlights?" or "I don't want microlights, how bout cash or other knives?"
The way I feel is simple - if I can't get a deal buying on the forums, I'll buy it at retail where I know I'm MUCH safer. If you're not willing to deal, then try ebay or something else. Even dealing face to face, you should never pay 95% of retail to a non-dealer unless you really really want the knife. Call me a vulture if you want.
Just my 2 cents - feel free to disagree. Also, note that I never lowball that badly (usually I go only a few dollars less than the posted price) - and this is usually due to my extreme lack of money. If I were weathly, I probably wouldn't give a d@mn. Of course, if I were weathly, I'd probably just buy it at retail.
-- Rob
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Me fail english? That's unpossible!