When I bought cheap daily car, I chose Honda Accord '93. Cost me 850 euros here, I don't know how much they cost in UK or if you get better cars for that money over there. It was realiable and with 290 000 km on the clock I didn't need to do any kind of fixing or maintenance. It was even pretty good car to drive for a jap car. Only bad thing was that it had only 110 hp (2 litre engine) and had fuel consumption of a V6. And yes, they do rust.