In need of phone & sound system
 

I have a 2006 C230 My radio has buttons for telephone. My owners manual says I need to purchase a phone craddle for it to work. Mercedes dealer says that I have to buy the craddle and pay $1500 for installation they where not very helpful. (does this sound about right?)
There is wiring in the center console for what I think it would go to the phone craddle. Has any body have any suggestions or any input on their experiences. Would really appreciate.

Also have a sound system I want to upgrade I dont want to change the factory stereo but would like to connect 3 channel amp and 1 12in the trunk circuit city had my car for 2 days and they called me and told me they could not complete the job because they said they wanted $600 compaired to $200 original price for installation. I do have some knowledge in connecting sound systems.But not to sure how to go about to connect it onstock radio without RCA plugs and by the way I dont know how to pull this stereo out.

Any help would be very appreciated Thank You.