It is best to let the car speak for itself. Employ the used car check list to observe and listen to the car. The negotiation on a used car is very tricky. How the car was cared for is as important as make and model. The newest cars have the greatest safety.
Safety is important.
The science of automotive safety is just a few decades old. There were improvements years ago, but nothing like the air bags, anti-lock brakes and reinforced structures of today. So buying used, as a rule, is actually buying less safety. Even if you buy a big used car, it's not as safe as a comparable new car. A used car will cost more time and money to maintain than a comparable new car.