Bored here in work and found this BMW evaluator on the BMW.ie website. It works out the cost of your car over a 3 year period and splits it into costs for tax, tyres, servicing, fuel, nct and depreciation.

Pretty handy tool! My 325 is working out at 15,000 over a 3 year period. They recommend a new 142 320i efficient dynamics for me and try to show that it would save me money which is not true with the inital outlay!