In addition there are a couple of other things I always check on when I do a service;
> Sway arm bushes: jack the back wheels off the ground and try to move the entire wheel unit 'on and out' of the wheel arch, if there is movement then the bushes are on the way
> Wheel bearings: Jack the wheels up and grab the top and bottom of the tyre, rock them over the centre, if you can feel clicking then you have a wheel bearing on the way out
> Thoroughly clean the inner rear wheel arches as these are a big unseen rust weakness for the b - in fact I bet a lot of people have this issue without knowing it!
> Clean the idle valve: Peel back a small section of the intake pipe just before the throttle body and squirt some carb cleaner in there while the engine is running, keeps things nice and clean and helps prevent hunting on tickover.
> Every now and again take the wiper arms off and dribble a little 3 in 1 oil down the splines, these are another weakness that rusts and when they do cost quite a bit to replace, they also have a tendency to burn out the wiper motors.
> Check the CV boots: the b seems to eat them and its less expensive to change the boot than it is the entire CV joint!
> Rear brake pipes: These get rusty so its a good idea to check them over and give them a little brush with oil from time to time just to stop them from disintegrating
I think that is about it (over and above the normal service stuff) but if I can think of any more I will post it up....
HTH