2004 A4 B6 Cabriolet Retrofit Radio
 

Hi Everyone,

For my first project I would like to retrofit my 2004 A4 B6 Cabriolet 1.8 with an RNS E or D Navigation Plus system. I currently have the stock Symphony.
Is this possible on an 04 Cabrio?
Also I've been looking online and from what I found the RNS Navigation Plus sell for around $800. I'd appreciate feedback on finding less costly marketplace.
There are also Android options for about half the price that offer what i'm looking for (CD, GPS, 4G, touch screen, Bluetooth) the UX is pretty juvenile though.

Thank You!