Help on a multi-room configuration

I am trying to amplify a multi room setup (4 rooms)with a total of 10 speakers (B&W) for 2 channel audio. I assume I need a high powered amplifier to drive all the speakers - does anybody have any suggestions for an amplifier. Would a high powered Crown professional amp be best????? I also need a speaker switcher - any suggestions??? My budget would be max $6000.

Thanks - Chris