I’ve never bought a new car, it’s just way too expensive in the Netherlands, especially with the added sales tax imposed on new or imported cars.
But try to read up on the model you’re interested in, because maintenance will be your new greatest cost, depending on the car, brand, model, engine, fuel type. There should be enough online resources (UK specific) that summarise these for you. Unfortunately I only know Dutch resources.
I actually thought Jack Black did a good job with claptrap. He was just as annoying, which is praise in this case.