Lowrance H20 Color with LakeMaster map (WI)
What is killing the price on these is the Navionics app for smart phones ($9.99) and the fact that they are discontinued and are basically to expensive to fix if they break.
I'd say if you get an offer of $150 for the GPS and chip it's a fair deal, if you have the 12V power cord then it's a good deal for the buyer. As they say you just have to find the right person.
What does the screen look like? Scratched?..If the screen's pristine I'd give $100 for the unit and chip IF you're local and I could see it before buying.
I'm sure someone would pay more but not a whole lot more.