I've always been more than pleased with eBay for both buying and selling.
However, I use due diligence and caution before I buy, and conversely, with in excess of 1000 feedback postings, all 100% positive, I can sell items and get a great return as the buyers trust my postings.
As a buyer, you must carefully examine the seller's feedback, view the photos posted carefully, and read the posting. After a while you will develop a sixth sense as to the valid, legitimate sellers, and the scammers.
Last month I found a factory fresh new, in the box Pro 2006, that's right, brand new as when they were first released. It even had the original 9 volt battery still wrapped in plastic. I purchased it for $50.00 and will keep it right in the box for now. Brought back memories of the first brand new 2006 I bought years ago for many times more than $50!!!
Paypal has improved immensely and if there are any problems whatsoever with a purchase you file a Paypal claim and they will protect you. It is actually to the point where eBay really favors the buyers now, and the buyer can do no wrong. That's probably how it should be.
Amazon is the same. They will back the buyer to the hilt.
Easy to bash eBay, etc., but if used properly they are just another tool in our ever growing toolbox for buying and selling our radio equipment.