How much is a good goat?

I'm curious, how does one determine the value of a good goat? Is it based solely on its physical appearance, or are there other factors that come into play? For instance, does the goat's age, breed, or even its temperament play a role in determining its worth? And how does one go about assessing these various factors to arrive at a fair and accurate price? I'm eager to learn more about the intricacies of valuing livestock, particularly in the case of goats.