We are about to buy a used car with cash. What is the best way to negotiate?

My wife was in an accident, car totalled, we received a check from insurance. We are putting our ceiling at $14K for a used car. I've heard if you are buying in cash that you usually have more leverage than someone buying through financing. If this is true, say we want a car listed at 16K, what price should we offer the dealer to begin negotiations?