Used Audi a4 vs Used BMW 3 series?

I'm currently looking into buying a car within an $8000 budget. I'm really set on a 2006-2008 BMW 325/328/330 and I know a lot more about them and what to expect than I do when it comes to Audi's. I've found plenty of used BMW's that would work for me and I know the reliability of these cars is amazing with meticulous maintenance.

However, I recently came across a used 2006 Audi A4 Quattro 2.0T which I've fallen in love with over my screen. The car has 117,500 miles, clean title, no accidents and has been religiously maintained (so the seller says). I'm wondering what the lifespan of this car is and how much maintenance/money I should expect to put into it. I want the car to last me through the rest of college (3 years). Also does anyone know if this year/model has an aux port?

Also, I live in Phoenix so the AWD isn't really that important to me.

And I know that I can get a newer Honda/Ford/Hyundai/etc within my budget - that's not my question.

Both cars will go 250k+ with proper maintenance, which isn't exactly cheap but isn't expensive either when you compare it to a 7-Series or A8.

06 was the first year of the B7 A4 so I would stay away from them. If you're gonna get a A4 get atleast a 07 or newer. First model years always have issues.

BMWs are prone to oil leaks and stuff which might end up getting costly, but if you end up just getting those fixed early on they will last you a long time.

It's really up to you. Both are in the same condition and both could end up costing the same, just get one you like and/or one that's fully loaded.

If the A4 has a DSG gear box look up those before committing.
If it is the ZF gearbox these are OK.
The DSG boxes have a very poor reliability on higher mileage cars. When they go the bills would make NASA's budget look tiny.

"Used Audi a4 VS. Used BMW 3 series?"
-- Owning a german car over 100K+ miles is a risk and this is because of their reliability. German cars can't be compared to a Honda for example, especially after 100K+. Yes a Honda does break down but its the repair and labor costs that makes these cars a pain to maintain. So if you are not financially in that position to bear such exorbitant costs, stay away from them.

I would worry about the Audi's turbos. (if those fail, expect a $1500+ repair bill)
But the BMW, especially the 330i, has a stronger engine (in my opinion).

If not, go and test drive them both and see which feels better for you. If you are unsure about the condition of the engine, have a dealer inspect both the vehicles thoroughly and base your judgment on what they suggest. If a car has too much problems, avoid.

"I'm wondering what the lifespan of this car is and how much maintenance/money I should expect to put into it."
-- Expect to set aside $3000 a year for either one of them; and better be ready for even higher than that.

"I want the car to last me through the rest of college (3 years)."
-- If its just for college, that might not be bad. Are your parents paying for it? It will get expensive for them. But if you are planning to keep this longer, not the best choice.

"Also does anyone know if this year/model has an aux port? "
- The 2006 might not have an AUX port, you'll have to get an aftermarket kit and use that instead. There are FM transmitters you can use instead. The BMW might.

"So the seller says"… Never trust what the seller says, your interests are not aligned. Always take the car for a Pre Purchase Inspection at your own tech or shop. Also, any Audi or any German car with 90K on the odometer is in the money pit time of it's life. My German cars all went over 200K but none of them did so for free. You are a college student which makes ANY used German car a really, really bad financial decision for you. Not what you want to hear, but the Gods honest truth.