I believe the price is set well.
To consider:
– GM made a lot of XR which were loaded with things like disk changers, sunroof and a 6 speed transmission. Are you competing with these? How many? What price?
– Are you missing exposure to buyers seeking these big Epsilon sedans by using Craigslist? Should you buy an ad on cars or autotrader? In example – I want to replace my G6 with a 2010 G6, I’m using these tools.
– Have you taken it to carmax or similar reseller for appraisal?
