Adding Sat Nav and Telephone to MMI

[Littlebec]

Hi

I've just bought a 58 Plate Audi A6 S LIne Le Mans Edition.

I was wondering if anyone knows if I can get the Sat Nav And In Car Telephone system installed as the previous owner chose not to have these extras when the car was new.

I have all of the buttons, but it just says the functions are not installed when I try to select them.

Could you let me know how easy / difficult this is and if it just a case of installing a disc.

Any feedback much appreciated!!

Many Thanks

Becky