Turbo's out
 

My 2002 A6 with 131k was smoking badly and losing oil like crazy. I was afraid to drive it so I had it towed to the dealership. After checking the car out they told me both turbo's were out and it would cost $6000 to replace them. I've looked at turbo's on the internet and oem's are $2000 for the pair.

Is this a common problem and does the repair cost seem high?

I have a 2007 a4 turbo (80K on the car)and have had the turbo replaced twice by the dealer ship
got it back and when I go up hills it looses power shakes & black smoke comes out the back ,
it would have cost me 4800.00 but the warrany was still in effect for one more week
It time to get rid of the AUDI

That's perfectly fair. The engine has to be removed to replace the turbos. Figure the labor for that, plus the price of the turbos, lines, gaskets, and whatever else, and 6 grand adds up fast.