A lot of cars in your budget will 'officially' do 60mpg, but if you want that economy in the real world choices are limited. You can, however, get a current-shape, used Vauxhall Corsa 1.3 CDTI within your budget and that manages a real-world 60mpg according to Real MPG users. It's not the most exciting car in the world and the engine can sound a little gruff - but it's genuinely very economical and there's plenty of choice out there.