I have a very nice Kenwood unit in mine which does cd, dab, Bluetooth, fm, also has useful features such as hands free calling and a great selection of audio adjustments to get the best sound from your specific speaker setup. If your not going to fit it yourself would recommend find a trusted local auto electrician, have seen halfords installers make a right mess of changing a lightbulb! Regarding the aerial i have had reasonable success with using a device called a dab aerial splitter which uses your existing aerial and has a small module that creates a dab and fm signal with the right aerial plugs for each..
