1. I've found CarMax to be very fair with regards to selling them vehicles. Process was easy and cash out the door is always nice. I've never purchased from them though. As for Saturn, they're now defunct. That was probably more to do with the quality of their vehicles in the past 5 years than the buying experience.

2. Don't waste time with phone calls. The classic way is dealing via fax, but now it's easier to use email. In my last purchase I knew the model and trim level I wanted, but didn't care about color. I emailed every dealership within a ~1.5 hour trip from my house and told them what I wanted and how much I was offering. I got someone about an hour away to agree. The dealer 15 minutes from my house agreed to the same price after I told them.