How safe it is to buy from ebay(locally)?

i sold a dvd player to a user on ebay. She didn't pay for 1 month. She said that after I ship the item to africa she would give me $500. Scammed. My daughter sold a vcr to a guy. The guy didn't pay for 3 months. And, she sold 2 PSP games. A guy bought never paid the money. Good thing is you can tell customer service and they will give the buyer a strike.