3Series

If you can swing it, replace the steering wheel, it will feel like a brand new car.
I've tried all sorts of cleaning etc. Nothing has come close to brand new.

I think you can replace the center console cover with new, but probably less impactful than a steering wheel you touch all the time.
You might also try contacting some local dealerships (doesn't have to be Porsche) to see who they use for reconditioning used cars for sale. They might be able to do a really nice job on the center console.
However, I strongly suggest a new steering wheel for a new car feel in a pre-owned.

subwoofer

A new steering wheel is an option. Suncoast has them for 1k. Can’t get a red one but I am fine with a black one or carbon fiber. Don’t know what it entails with the swap? I will ask the dealer if it comes to that. I think the airbag has to be moved over.

I can't say the previous owner trashed the interior but it certainly wasn't cared for and it won't be like a new car regardless of what I replace. For example, there was this minor seat wear at the shoulder bolster on a one year old car. I had that fixed.

3Series

Yes, you re-use the airbag.
Dealer can do it in 20min, they'll probably charge you an hour. Ha.
You can do it yourself, instructions are readily available.
You'll probably need to buy a specific socket to remove bolt holding the wheel on, it's a spline.