Other than ordinary running costs,
Air-Conditioning (£800)
CAM Belt @ 80000miles (£300)
Electric Window (Passenger side)
Car is very nippy if you know how to drive it. I raced a 2003 Honda Civic 1.6VTi, the acceleration was almost identical, I beat him on the gear change as the clutch is very good. Handling is very good. Petrol consumption could be much better considering it is only a 1.6; with A/C on before a service I was getting barely 300miles to the tank (~55litres), after service more like 375 miles to the tank.
Air-conditioning should never have gone, I would never buy another Audi, knowing that after 5 years of use the A/C would require £800 to be spent on it-which was the only reason Audi servicing could give me other than lack of use (Although it was used nearly all the time!)
Re air con. I think 5 years of constant use is very good! The mistake you made was going to the main dealer to get the job done when there's plenty of specialist air con companies with keener prices.