Phil, he'd better be paying you
...no, seriously. On an Audi you should always start with a scan for stored trouble codes (VAG compatible diagnostic scantool), and Audi uses triple-square fittings on just about everything, so you will need triple-square sockets or similar to remove oil plug, underbelly splash pans, brake rotors, and event to access the cabin filter box (under the glove box). Make sure what engine is in it; TDI engines have very specific oil & filter requirements, for example, and if you change any driveline fluids under the car (the diffs & transfer case are dead simple to drain & fill while splash pans are off the car and it's slightly lifted for access/clearance under the car). Be absolutely sure to verify the proper spec fluid required for the application on these cars, and use exactly what is specified.