Ebay reputation
Ebay has installed a far from perfect but doable feedback-system. Some buyers (but also sellers) use this "Member Profile" to prove that they are trust-worthy.
I am not going to go into detail on how to read these profiles. But one tip for sure: Don't just look what the score is, also check, since when this buyer/seller is active on Ebay. A seller / buyer with a 100+ rating which has only been active for a few weeks, is just as good as one that only has 10 positive (and 0 negative) feedbacks, but has been with Ebay for years.
HOWEVER: If somebody shows you a feedback rating that is good, MAKE SURE it is really his'!
Nothing is easier that to look up a good member profile on Ebay and claim it as yours: "Look, I have 100% good feedback. Trust me."
So how can you check, that the person you are dealing with is really the one with a good feedback?

Simply go to the feedback profile and use the "contact member" feature. You will have to sign in at Ebay, but if you don't have an account yet, it is worth doing that anyway.