You will usually be able to get the best price for your car by investing the time, effort, and money necessary to sell it "retail" to a private buyer/consumer---someone who doesn't plan to immediatly resell it.
You will have to develop an effective classified ad, place it, make yourself available to handle phone inquiries, appointments (and no-shows), show and demonstrate the vehicle to serious and not so serious shoppers, negotiate over offers, and worry that the check will clear.
In addition, it is a comment on our times that in considering how to sell a car, concerns about security are increasing not far behind considerations of price vs convenience for men and women of all ages. Retailing your car usually means meeting strangers at your home (often in the evening when it may be dark) to show the car and accompanying (him? them?) on a test drive. Many sellers with concerns about security have adopted strategies like showing the car only on weekends during the day and having a friend or relative present. Still others feel that concerns about security tip the scale toward selling the car "wholesale."
Selling a car "wholesale' is selling it to a car dealer as a trade-in or to an auto wholesaler---in either case, to someone who plans to immediately resell it. The dealer or wholesaler will need to purchase your vehicle for substantially less than you could probably get if you sold it yourself. Otherwise the dealer will not make enough profit when the vehicle is resold. And if the dealer doesn't think he/she will realize enough profit margin when reselling your car, he/she won't buy it from you at all.
From carclub.com - Consumer's Guide to Selling Your Car. http://www.carclub.com/new_used_cars/used_cars/consumers_guide.html
