It all depends on what things are selling for on the local market but sometimes people over pay for something then when they go to sell it they usually ask too much for it.What's frustrating is when you see an item here in the classified that you'd like to have but they're advertising it for what it would cost new....or often even more. There's an item on the site right now that I'd like to have but the owner has it offered for $300-$400 above what you can see them going for all over armslist. Now that's his right but I'm less inclined to make an offer, since it will most likely offend him. Sometimes I'd like to go cut and paste all the links to similar items just to prove the point but I'm sure that would be seen as improper etiquette also. You can't help but wonder how some of these guys come up with their offering prices. Maybe they don't have internet and can't research and actually see what the market value of their item is? I think most likely it's the, "this is what I have into it so that's what I want out of it" mentality.
These people probably don't research prices much, or they just have to have it now, so that's why they over paid in the first place. These people are pricing their used stuff based on what they paid, not necessarily what it's going for locally.
Sometimes it's trying to take advantage of a buyer that doesn't bother researching local pricing and is willing to over pay.