I'm finding that these cars are perfect for the home mechanic. I feel like I made the right choice on a car model to cling onto (before I make the leap to electric). The car is fairly easy to work on especially relative to smaller Audi's with the same motor. Most things (that aren't plastic) are solid and will last a long time. The car drives well, is safe and quick, and also looks quite handsome. The cars are also fairly inexpensive to purchase due to the high costs of maintenance and ownership. So the mechanically inclined are in a position to save a good coin on them. Especially if you have other vehicle options at home.
There are a good number of modifications as well as parts available from other cars above and below this line as well as parts from other years and makes. Vag-com allows for some cool modifications and 3G MMI is available on 2010+ cars. These were 60k vehicles when they rolled off the lots a decade ago, so they start off life on a really good foot. It also doesn't take much cash to boost the car another 100HP if you're into that sort of thing (the 3.0T anyhow). If you find a specimen that was well cared for, and continue that, they can comfortably last a long time. Window tint, paint care, and shaded parking will go a long way.
My car is up to 120k miles and I am in the process of doing a major maintenance. But doing the work myself and taking my time, I am saving thousands and will have a solid, dependable beast in my parking spot. I'm planning to take this car to 250k+.
EDIT:
Check the car for oil leaks, ask for service records, make sure the transmission is in good shape and that the pipes don't have too much black soot on them. If it's an Avant, check that the MMI works and the bose amp hasn't been leaked on from the rear window washer. If you can, hook up a Vag-com to the car and check the timing marks (I believe it's block 93) to see if the chains are wearing.
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