If you are using chrome, there is a nice extension available on the chrome store that displays you information about the seller (looking up other products and ratings from him) and especially useful it displays other products it finds with prices and price history chart. The history part looks like its generated by the users of the extension and saving the data to a specific listing whenever a user navigates to it, hence you don’t have all data but if you regularly go to a certain product and want to see changes without having to note them down, this is handy.
How it looks like
In case you don’t receive the order (this happens sometimes) and you see the purchase protection running out, you have to decide what to do. In case I ordered it just to play around and don’t urgently need it, I usually write a short message to the seller that I haven’t received the item and if he can extend the purchase protection accordingly. You need to keep a watch on the purchase protection end time because after this, the order will be automatically closed and a refund / resend will depend on the seller willing to continue business with you.