MINIs hold their value well and you can buy a five-year service package for just £200, but quite a lot goes wrong with them. They now have a new chain cam BMW diesel engine rather than the Peugeot belt cam diesel previously fitted. If looking at MINIs, I'd also look at Fiat 500s. The petrol versions seem to be almost faultlessly reliable. The diesels can have DPF related problems, but are extremely economical. Another nice little car is a Mazda 2 1.3TS2. Not quite lowest tax, but 45-50mpg, delightful to drive and reasonably high-geared for the motorway. It's getting a facelift in October, so you might get one now at a decent discount.