Peter, like John I have a Sony MEX-BT3900U bought cheaply from Halfrauds. It comes with its own remote and has bluetooth, ipod, ipad, usb and various other bells and whistles of which I am ignorant. Very easy to fit. I put all my music on a flash memory stick and use the remote rather than mess around with CDs.
I think I paid about 100 quid at the time.
