BUYING ADVICE 2007/2008 Cooper 1.6

[hunt205gti]

Hi, I know very little about these cars and my wife is looking for an 07/08 Cooper 1.6. Are there any problems that I should be looking out for on these and are they generally reliable.
Any guide on running costs and what they are like to drive would be appreciated.
Current car is Swift 1.5 which actually drives pretty well and averages 43mpg.
Budget £6K max.
Thanks