working at a dealer....i hope I can give a little insight.
what kind of car are you looking at? makes a huge difference!!!!
Price is probably a huge factor, but so is mileage and condition.
Feel free to pm me. I can run a carfax for you if they will not offer one.
Line up financing before you go, and DO NOT allow the salesman to steer the conversation from price of the car to monthly payment. Run your fingers along the edges of all of the panels, easy way to detect paintwork.