They are right! The more dealers, the more calls, the more research = the best deal.
I just bought a 2011 328i xdrive coupe (all packages except sport) with 7k miles for 32k.
I made lotsxof calls, I had multiple dealers calling me back, and emailing me back. I used one dealer against another (and you can't make stuff up, because they Will check on the other dealers to see what they show).
I had emails coming in at 8pm with lower prices.
I was willing to travel which helped, and ended up going 6hrs to get the car I wanted for the price I wanted.
I was also willing to walk away if the car wasn't right.
Two straight months of searching Cars.com with the very specific colors and miles I was looking for paid off. Like most things in life - take your time - never ever feel obligated - and set your terms and don't budge. You'll get what you want eventually.
I waited two months for a dealer/seller to drop their price on a consignment BMW motorcycle. 2 months equalled $3k.
Take your time