http://g35club.org/sedan-main.shtml
The above link has information pertaining to the '07 sedan. The models for '07 are standard RWD, RWD Sport, AWD (X). I currently have a '07 G35 Sport that is loaded and the trade-in value is just over 10k with 105k miles....but that IS a loaded model (premium, nav, tech, 4-wheel steering, spoiler, etc.). Obviously selling by private party would be more than the 10k. Go to KBB.com and plug in the information to get an idea what it's really worth.