c1 are due at 10 000 / 1 year
c zero I think is 12 500 / 1 year (we don't see many of those) - I'll check when at work.
If you have a C1, expect to pay about £175 max, or take it to a toyota garage and pay £99 ( same price as the Aygo - same car)
Let me know if you need more info - I work at...