Petrol Highest Mileage?

[OvSeer]

Hi all, I'm thinking about getting an Audi A5 Coupe, the problem I'm having is that I live quite close to London and I'm worried about the diesel laws that might affect me if I buy a diesel.
I'm wondering what kind of mileage I can expect from an A5 Coupe TFSI 2.0. (2009 plate )

I'm looking to spend about 5K on it and for that price the mileage is around 130 to 140K obviously it largely depends on how it's been looked after but what kind of mileage have you guys gotten out of yours? and do you think it worth buying?

Thanks!