Craigslist vs Kelly Blue Book cars?

So, for example:If Kelly blue book states that a specific car (say a 2003 Ford Taurus) in Excellent condition is worth $2300. & on Craigslist list some is selling it for $4000. Would they be moded, and or willing to negotiate their ridiculous price ranging, to sell the car for just a little over $2,300 say $2,600? In all technicalities that is what they are looking for, and after half a month has gone by they realize no one will want that, so they keep lowering prices, in reality they want it for $2,600? Or more right?

If I confront the situation with Kelly blue book, and offer them a little higher price, is that what the people in this mind frame would be willing to do?

Just confused as to why they are selling 2003 Nissan altimas for $5000

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