You can't drive anything for free.  Rocker arm?  This ain't no pushrod
engine!

You want to trade to a BMW, and want "more reliable?"  Uhhh, no.

Timing belt is maintenance.  Needs to be done on any car that's got a
timing belt.  Has nothing to do with reliability.  Seals?  They do go
bad in any car, but they seem to go bad more quickly in Audis, for
whatever reason.  Get them replaced during the t-belt replacement.  The
whole suspension needs replacement?  I doubt that.

So, you could sell it now, honestly, for about $6000-8,000 (ball park),
or fix it and drive it another 90k miles and not have to think about
any of those things.

Or trade it in for a different set of hassles.  The kind you get with
just about any other car.

If your main goal is reliability, go Toyota or Honda, and stay away
from BMW and Subaru.  If you want the same kind of driving that you get
with your Audi, you're not going to get it any cheaper than fixing your
Audi.

My suggestion?  Trade in your Audi on a Honda or a Toyota.  You'll be
much happier about repair frequency and cost (if you're like the
majority of folks who own those cars.)

E.P.

Figure a timing belt/water pump, suspension fix, tune-up is 4 or 5 car
payments.

With the 330Xi, you still have another 32 car payments (assuming a 36
month note).

Assuming the car has been taken care of, you should be good for awhile
.... save up a few car payments (that you aren't paying) for the next
repair.