If you are doing high mileage then you would choose a hard wearing tyre like Michelin (my bosses car has Michelin Pilot and he got 50,000 miles from all four tyres, driving like an idiot).
I wouldn't buy a car which had tyres on it that I had not heard of, or if every tyre was different. If the tyres are cheap then was the owner also using chip fat for engine oil or washing the car with washing up liquid etc etc.