Buying a 2012 Toyota Prius c, and saving $1000 off of MSRP.
The Prius C has a small profit margin to begin with and when I purchased the vehicle they already had a $500 off sale and I negotiated a higher price on my trade-in so negotiations on the base price were slim to none beyond that point. However I would say that by letting them know that I had the WPR for the vehicle, that pricing discussions were very straight forward and to the point with no fluff added to confuse you. By having it in my arsenal of negotiation papers I felt like it has helped me.
Brian was very straight forward and honest in his dealings with me. He is a salesman and has a job to do, but didn't try to push unnecessary options or try to push me within a price range I would be uncomfortable in. It was a very complete transaction, both in financial discussions and in his (correct) knowledge about the vehicle and how all of the functions work. I would gladly deal with him and the dealership again for future Toyota vehicles.
Buying a 2011 Toyota Camry, and saving $4000 off of MSRP.
I and the salesperson worked from the same info base for a change, the invoice price, so the only thing left to negotiate really was the profit margin. Factory Rebates were automatic. Never was the case in the past, invoice price and rebates always hidden in the past.