In the last year, I’ve bought 3 vehicles (2 used, 1 new). In each instance, I found the car I was looking for at an out-of-town dealer, so I called them and told them what I was willing to pay for an out-the-door price; and then basically ignored them. I typically went really low, thinking I’d never hear from them again, but after a few days most of them were calling me and working to get the deal I wanted. I ended up within a few hundred dollars in all three occasions and walked away with a deal that was better than what average people pay according to truecar, etc. websites.
The Two main things, IMO:
1. Do your research (blue book value, car fax, etc) - sounds like you already are.
2. Be PATIENT! If you don’t play their game, they will come calling; especially next week as it gets closer to the end of the month. I’ve walked out of dealerships before over a few hundred dollars where they refused to come down to my price but ultimately I ended up with a better car for a better price somewhere else.