I wouldn't buy one if it's going for something as cheap as 10 dollars or something, but some of them are real, or close enough. Check out the sellers feedback always always always. Its the best way to feel more confident about what you are purchasing. See if they have an insurance option or a return policy. Communicate with them, send them messages asking lots of questions, and ask for more pictures of the actual product you are getting if the auction shows only a generic picture. If the price is reasonable, they have good feedback, and are willing to work with you and communicate with you then your chances of being screwed get lower and lower. And insurance/return options are a great plus.