Need help with selling a used car!!!

In my quest to sell my 2012 Range Rover sport I began searching around for alternatives to dealerships, Craigslist, Ebay motors, etc. During this search I stumbled upon Instamotor, Shyft, Carlypso, and Beepi. Each company promises to revolutionize the used car buying/selling experience and they have slight variations from each others business models. However, Instamotor seems like the best bang for my buck as they offer a lot of free services and don't take a portion of the final sale price. Making as much money from this sale has always been my primary intention and why I avoided dealerships and low ball offers from CL in the first place. I'm curious about the company and want to know if anyone here has used their service or heard of them?