Having read the replies, I have to thank you for making me lots of money.
I have written out lots of messages on scraps of paper (paper you would find lying around your car) and they all say.
SO SORRY, I accidently bumped your car but I cannot see any fresh marks. However, I expect you know you car better than I do, so could you have a look to see if there is any damage which I could be responsible for?. If so, please contact my Solicitor when you will be assured of compensation to repair your car. Please quote today`s date and ring them on 0870xxxxxxx.
Luckily I had the forethought to arrange this premium number and they should only pay �5. or so and leave a message.
I am now off to put a few hundred on random cars in Golders Green, and although I confess to putting ideas in their head, as hughie says - they will not take advantage, will they?