I purchased a 2007 E350 a few months ago. I noticed a cradle in the back side of the arm-rest which the salesman told me that all I needed to use the voice command for my bluetooth phone and controls ( I guess he was referring to the stereo/CD) was an adapter for about $300 online. I am not up on this because my Lexus I had for 6 years did not have that option. Can someone please tell me what I need to purchase and what functions will this provide? Any other suggestions? Thanks