My partner currently has a 2005 Mk3 Ford Focus 1.6 automatic. The fuel economy is terrible, averaging sub-20mpg. She does several short trips per day for the school run, each trip being about 2.5 miles six times a day, plus other short town driving trips totalling about 180 miles per week. She needs an automatic so I have been looking at small diesel automatics such as Toyota Corolla 1.4d automatic, but I have now been advised that diesels would not be good on economy on such short trips. I have a budget of about £5500, but do not know whether to buy petrol or diesel. The £60 per week petrol costs at the moment are too high.