There's a difference between Audi service indication and ODBII check engine light. Check engine light can be reset by regular ODBII scan tool. If you are talking about Audi service indicator, you would need Vag-Com tool:
http://www.ross-tech.com/
I have one of these and they are worth their cost. It tells you a lot about the car. It recently saved me few hundred dollars when I was able to repair my own MAF sensor (clean it instead of replace / repair). But if you are not the do-it-yourself-er then... you have almost no choice but deal with the dealer. There's no free ride in the world of Audi. The only choice are expensive and more expensive repair cost.
As I see it, it is worth the money given I can resell it when I get rid of my car later. So the actual cost would be the difference between buy and sell price. And the difference would be much less than frequent visit to my Audi dealer.
Good Luck.