Kinks can happen for two reasons: genetics and an injury. If it was an injury and doesn't affect the quality of life or breeding of the snake, I don't see a problem with it.
There's nothing wrong with looking for a good price, just remember that others might not want to wait for a better price to get that nice snake. Also, there's no such thing as a "perfect" snake. Snake quality is very subjective. People like different qualities in a morph, and what you may think is perfect might be unappealing to someone else. Pay what you think the snake is worth and what you can afford.