1. When you're shopping online you need to be sure you know who you're buying from. If you're buying with an online auction site, only order from people that have positive feedback. On other sites look to see when they are a reputable company by looking for reviews to them online.
2. Be sure that you're entering your payment details on a good site. Look for "https://" inside the URL from the site that you're seeking to buy something from. If you don't see that or no indication of any website security, then it's probably a wise idea not to trust those people with your account information.
3. In order to buy a used product online, learn more about the vendor first. You need to visit their profile and search for reviews published by other shoppers who bought products from this seller. Usually do not hesitate to contact the seller to ask a few questions about the product you are considering.
4. When you shop online, be certain the site you might be on starts off with "https". The "S" signifies that the site is secure, which entails that one could safely enter your personal information without having to be worried about identity theft. When a site does not have the "S" in it, you might like to avoid using it.
5. If you're considering buying a product online, look into the reviews. The reviews from other people that have used the product will be able to give you a good idea about the product. You might be able to find out the quality of the product, if this worked as described, and if you should make the purchase.