Sounds like you aren't very well versed in the value of mechanical stuff. That's why kbb or nada is good to look at. You're wise in catching that it is not worth double of kbb.
Don't think dealers will have it priced to sell. Dealers price to make money and then price to sell if it doesn't sell. Sometimes it doesn't make sense.
Keep using kbb and also ask values on here. You'll get a wide range of answers from realistic to wtf? But filtering out the extremes and bs you'll find he right price.
That and compare relentlessly. Craigslist is a good resource for that to look in different areas.