> These extra items add to the cost of replacing the timing belt, however, they
> insure that this area of the motor will be good for another 6 years or 90,000
> miles.

And more importantly, replacing the water pump etc. require you to
remove (and thus replace) the timing belt, so unless you are sure that
your water pump etc. will last until the next timing belt change it
makes good sense to do it all at once when you are already shelling out
the big bucks for a TB change.