firing on three cylinders - should I avoid this car?

[Anonymous]

I responded to an ad in the local paper and the lady told me someone had looked at her car and apparently there was a problem with it. She was a bit vague but said that she'd been told it was only firing on three cylinders. She is having the car fixed. As a prospective buyer how concerned should I be? Is this problem symptomatic of lack of maintenance? Or does something in the engine just need tweeking? If the car is in good condition the pricing is very reasonable. I didn't ask her to call me back when the problem was fixed. But should I have?

Thanks,

James