bmw 320d rip off?

Hi, my dad has a three year old BMW 320D saloon and (just after the extended warranty expired) has been told that he needs a new dynamic stability control unit which would cost £1800.

This does not seem right?!

Im not sure what that is converted into $$$ but 1 you do have a BMW so everything on it will be expensive also i would try shopping around for other places and see what kind of prices they would give you....