My father is selling his as new 14mm Nikkor AF lens and asked me for advise on how much he can ask for it. What is, or rather is there a general consensus or rule about how to determine the price of secondhand equipment? It's a lens that he used only a few times for interiorshots, and it looks new. No scuffs or marks and the glass is still in perfect order. I know that on auctionsites it's more 'what one is willing to pay' that determines the sellingprice but I am not sure he is comfortable with going international with an auction. I could probably convince him offering it here first Thanks!