It's not a £500 car in the condition it's in. I'm swapping because a bigger car is better suited for my needs at the moment. With living on the farm and working up at a garden centre I'm always hauling around crap and people, and I'm nearly always thinking "I wish this had more power/space". I love the Micra and if I could keep it as a second/project car I would, but finances don't allow at the moment unfortunately. 
Thanks for the tip, I'll add a location.