It’s a Volkswagen under the hood. Besides some “performance” components most are going to be exactly the same as a Volkswagen.

Depends on what engine you choose… you can get a base model that has an identical simple and reliable drivetrain to a Jetta or Golf, or some exotic engines that are very costly to maintain- like the V6 TDI.

Maintenance on an older Audi is expensive compared to, say, a Japanese economy car, but you're talking maybe $1k/year to maintain on average, vs $500/mo payments for the cheapest new car.