In reply to t_hume:
Sounds right to me. Its a PITA if you pay for a cambelt and then the water pump goes.
I often find genuine dealers cheaper for these jobs as they appear to have fixed prices (set by the manufacturer?) , worth asking.
Also, possibly a better guarantee.
I like to think the prices are subsidised as recompense for whoever thought it a good idea for modern engines to rely on rubber bands.