Yep, 'Walk Away Renee' and the car salesman in his safari suit and white Gucchi shoes will chase you out of the yard with a better offer sometimes. My trick is..Go get all the new car brochures, Hyundai, Mazda, Toyota, Ford, Holden, Nissan, etc, arrange them all over the interior of your intended trade in, just pretending to the salesman you are looking at all models, sucks them in sometimes, sometimes I said.
When I bought my wife's new Hyundai Accent late last year, I put the Toyota Corolla/Yaris, Kia Rio, Mitsubishi Mirage, Harley Davidson, Honda Jazz brochures on the passenger seat, telling the car salesman I was interested in several cars, but as Dazz said, 'Change over figure on the trade in - Nissan Micra ST-L was paramount. I reckon it worked, got a decent deal.