Cambelt doesn't fail on the 1.9 but the water pump does and shreds the belt, personally I would do the belt and pump every 60k which for a complete kit and dealer rates expect to pay in the region of £400-£500, obviously less for specialists and a good Vauxhall, FIAT, Alfa specialist could do the job too so you could get it done for £300 (don't use cheap or non-genuine parts though!).
The good thing about that engine is that the design means that in the event of a cam belt failure pistons won't hit valves but will still cost in the region of £600-800 to sort.