i purchased a used fiat punto 2 weeks ago and so far my son has fallen out of the back door where it did not close properly,i had fixed,the electric window has stopped working,the exhaust pipe was rusted which i have had replaced ,the 2 front tyres were bald,which i had replaced,just checked oil which was dry so i have put that in,i am now feeling that i have brought a dud car what are my rights to getting a refund it was brought from a dealer for £1100 please any advice would help