I would suggest running through quotes on the comparison site in order to determine which is the cheapest. However, please consider the value of insurance and don't just choose the cheapest if it's with a rubbish company. The latter will probably fall on deaf ears though.

See the following link for more information on car groups: http://www.parkers.co.uk/insurance/

based on the little info you have given id say it would be more likely to be an insurer like quinn direct

They came up £80 cheaper than anyone else for my 24 yr old wife just passed her test!!

It does also depend on the car so id say a 1.3l engine or lower and if you can find a old but well mainted car like a ford fiesta or citroen saxo then all the better.