Patience, thorough research, and the willingness to go as far as it takes to get the right deal.
I've traveled 600 miles just to get the deal I wanted. I was willing to go a bit further. The result of that was a 2019 bike that sold for 11,9, it was a dealer demo and already broken in, they did the first service for me.
With 650 miles on the odometer, that saved me thousands off the sale price. BMW does promotional stuff too!