sellers trying to sell used product for 10-20% off of list price

"Can always go down but not up as a seller."

That is what I thought until recently.

A friend of mine was selling a car asking $6000. It was, by all accounts, as low as anyone could ask for it. The car was nothing fancy and is relatively rare on the streets. To make it even more unusual, it had manual transmission. If you wanted that kind, you really had to look for it and wait until one showed up. He posted ads somewhere, Internet and some print. Three phone calls. Everybody wanted a discount, offering $5000 or so. He did not budge and gave up the idea of selling it.

A couple of weeks later, another friend, more experienced with car sales, told him to list it for $7200. "Barely anyone was interested for $6000 and nobody wanted to give that much, who would be interested at $7200?" Still, he listened and listed for $7200. He was overwhelmed with calls. People were insisting to buy it, sight unseen. In the end, he told three first callers/prospective buyers that the first one to come to pick it up will get it. The buyer said he had been looking for that kind of car for a while. It sold for $6500 and the buyer was very happy to have gotten a discount.

I completely agree with the OP. The B&M shops I frequent I'm up front with so I don't waste their time and they can show me the products I can afford, floor models etc. When I see used items here for -20% I just assume they're new to the game and the lowballers will straighten them out. Shipping, paypal, and AG fees will add at least 10% and around here most dealers charge exactly 50% list for used trade ins. 

iv'e been trying to buy second hand nighthawks for a few months
most sellers asking 200-300 for a used pair when they are 250 new with free shipping.
so i gave up and bought an open box item with warranty for 200 . i like the audiogon board since i can always make an offer.
when i bought my guitar amp it took me 8 months (almost everyday at reverb and ebay)to find the right amp at the right price .be patient and make offers if you really should have  it will be there at the right condition and price eventually(i hope...).
loved that guy who said he could smell you....too many years serving costumers so when they are outside the store they can unleash that pure hate that's been building up 

following my watched list, I'm often shocked how high some used gear sells for, as well as how many low ball offers are accepted...there is a surprising amount of year old gear at super high prices...but there are also a lot of amateur sellers as well as sellers simply expecting an offer well below their asking price...as said above, make an offer or pass it by...

I agree with Roxie.

Selling an item less than a month old doesn't warrant 50%.  If they don't like buying something practically new then let them go to a dealer and pay for it.