With a small budget, I'd be looking for a Ford Fiesta, Nissan Micra or Toyota Yaris - all are tough little cars and there are plenty around. Don't concentrate too much on a specific model, though. You'd be better buying whatever's available in good condition with a long MoT. And avoid dealers, they'll be selling scrap at this money. Just make sure whatever you buy has a proper service history so you don't end up getting a car that will soon have its fair share of issues crop up.