Try to get a service history of the car to find out what has and hasn't been repaired since it was new. The more work done, the less you have to shell out in the near future. Check for frequency of tune-ups because an engine that runs efficiently is subject to less wear. The timing belt should have been replaced a few times as well, depending of course on the age of the car and the number of kilometres on the clock. The cooling system should have been flushed regularly as well.
Fuel injection is the best form of fuel delivery for street use today.
It marries high performance and fuel economy, two words not often used in the same sentence before fuel injection was developed. Volvo incorporated several different Bosch injection systems into the 240 line. There is a label indicating engine type on the driver's side shock tower. Consider your performance requirements while checking engine type. If a high-output engine is a priority for your next 240, a turbocharged model might be right up your alley.