I have a 2001 A4 1.8TQ & had it for 6 or 7 years. It now has 153,125 miles and running like a fine swiss watch. I use Mobile 1 0W-40 and change it 2 or 3 times a year myself. Car all stock, been on track 3 times. I have spent some money on it but not unreasonable.
2007 (car 7 years old) $619 all maintenance & repairs
2008 $1213 (incl new tires)
2010 $2469 (steering rack $1382)
2011 $2645 (new tires, oil pan [my mistake])
2012 $300 so far this year
$30K for that car is pretty good I think; trade it after about 6 or 7 years. Some of my problems may be due to cold salty winters