Berlingo?

Even at dealer forecourt prices you'd get a 6yo second generation HDi for that money.

Surely, an almost impossible question to answer except....if you buy a car privately at that price without knowing its provenance then it's probably complete pot luck.

I would keep your options open regarding make, model, age etc, take someone who knows about cars (to check the basics) with you when you go to view and go by gut instinct regarding who is selling it. Ask as many questions as possible and see if the seller replies congruently.

Also, what's the definition of 'cheap to run'? If I were planning to keep my 9 year old A4 Avant for the foreseeable then I would expect to pay an average of £300 per year for servicing and tyres, and would budget another £300 per year to fix unexpected problems. But that's only because I've had it from new and therefore know its history and how it's been driven.