2012 Audi A6 3.0 Premium Plus.

Greetings, I'm looking at this vehicle and am wondering if there are any known issues with the engine and/or car? I've been driving my 98 B5 Passat for 16 years, figure it's time to replace her. What kinds of issues and maintenance costs can I expect if I purchase the above?

Any and all information appreciated,

Thanks,

John