I've been using EBAY now for at least 4 years, and can say that I have had many pleasant experiences, and a number of experiences that have made me want to close my account altogether.
Remember what you see advertised is not always what you will get. If at all possible, pay with PAYPAL. At least you will have minimal protection if the item does not arrive. Forget it if the item arrives damaged... You've lost your money. Unfortunately you will be asked to get a professional opinion on whether the item is damaged which will cost you more than the item was worth., and PAYPAL charge to recover your money!!!!
Read the sellers feedback. If you see a number of Negative Feedback items AVOID! Unfortunately EBAY is full of scammers and crooks, so you need to read carefully, and ONLY buy from EBAY'ers with good feedback. EBAY do not remove the crooks. There is no three strikes are you are out. The crooks are free to trade and will take your money. Report all bad deals straight away. Give the seller the opportunity to resolve the problem within a reasonable amount of time, and if it can't be resolved, ALWAYS LEAVE NEGATIVE FEEDBACK. If buyers read the negative feedback, hopefully people will not trade with the crooks.
There are many traders who value their feedback, and will do everything possible to resolve a problem. There are many out there that'll just take your cash, and be off into the night!!! As the old adage goes ' You pay your money, and you take your chances!!!'