Audi Forum - Audi Forums for the A4, S4, TT, A3, A6 and more! - A4 Avant 2004 Keep or Sell? Advice needed.

Hi, I'm new to this forum, but I've owned Audis for 15 years. This one, I bought it in 2007. It has 177K on it. It hasn't seen much use for the past few years, and I've only given it "life support" maintenance. It isn't my daily driver because I don't have a daily drive. Our "main" car is now a Volvo S60. I meant to sell this A4 a few years ago, but just... didn't.

So now I have a small dilemma. I like it, and am thinking of keeping it, but I'm not sure if it's worth the effort to fix, or if I should sell it. And if I sell, what is a fair price?

Pictures below, but here are the known issues today:

Rust - R front wheel arch, spots elsewhere
R Front door blade is bulging (rust underneath?)
Rear diff is seeping (not leaking)
Throws CEL if not fed the most expensive gas
Rear wiper was vandalized & torn off
Has a tendency to destroy window regulators (recently fixed)
Will need timing belt/water pump service soon