£7.5k will get you a well serviced example if you want the petrol. Big engine, low economy, high service bills all make it a tough car to sell, so you'll have a lot of room to barter.

Anything that old, regardless of its service history, is still going to need ongoing (expensive) maintenance. I've spent around £1,400 (independent garage) on mine in just 4,000 miles. I suspect I'll be spending another £200-400 next year on bits and bobs.

As mentioned, ultimately it doesn't matter what the mileage is. The key is that it's been well looked after. Mine has BMWSH up to 60,000, then was owned by a mechanic who did all the work himself before I got it. Despite this, it's still needed the aforementioned amount of money spent.

I'm sure you're aware too that you will average 18-20mpg at best. £5 petrol will take you the grand distance of 15 miles.

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BMW X5 4.4 2004