Audi Repair: Audi ABS and brake sensors, general mechanic, a6 audi

Question
My A6 Audi wagon's ABS and brake sensors keep flashing and occasionally beeping.  Some times it goes off indefinitely.  My brakes have been replaced by a general mechanic who says he does not have the appropriate tool to change the sensor but assures me the brakes are fine.  I have quit going to the Audi dealer's mechanics because I have had some extremely questionable service problems, feel unfairly charged and even have had some shady unexplained damage done by them that I feel would not be handled in a truthful manner on their part.  My car is 8 years old and want to keep it running smoothly but at a fair price.

Answer
Sounds to me that you need to change mechanics and dealer.  Any mechanic should have the tools to check the sensors.  If the dealer is not doing a good job, I would check out some other repair agents.  There are good ones out there, once you find one, keep going there...!  I have brought the same car for estimates to three different places, to be told three different things.  Keep getting estimates until you either get the truth (if you know it) or a believable consensus... Let me know what you find,  Jan