Any ideas on what a used fish finder is worth?

[chrispbrown27]

Two years ago I bought a Humminbird 571 hd di fish finder for my boat. In the past two years I have put it on the boat (kept in my truck the rest of the time) a grand total of two times. My uncle is in the market for a new fish finder and I mentioned that I might be willing to sell mine. He is interested but I have no clue what it would be worth. I am pretty sure when I bought it two years ago I paid around $240 for it. The prices range from $199-$299 for it now days. I have seen none being sold used and the closest I have seen was a 581 hd di, which I believe is the color version of the one I have. Anyone have any idea what a fair price would be?
Chris

 

[cocopuff]

They are on ebay for $70 buy it now price. Depends how much you like your uncle
Maybe 30-40 bucks

 

[JoshKeller]

start at half retail and be prepared to drop if needed