A rather bad experience on eBay
I have used eBay to buy some tools and a few lovely digital cameras. No problems until I needed accessories for one. I goofed in that I made first purchase before camera arrived and based on info I found both on eBay and Internet so I had the wrong battery and a very generic charger for all cameras but not recommended at all by manufacturer of camera. I opened things to see what I had (the hard plastic bubble packages can be very difficult to see what you have sometimes). Everything was wrong. I requested a return (I've never had problems in this regard). Because I opened stuff and could not return in original shape, they refused. They did tell me they would take two batteries back (but not charger) and discount 20% plus I'd pay postage. They would send me that manufacturer's battery for a HUGE amount of money. I didn't bite. I decided to try selling myself like on Amazon.com.
Reading the site gave NO clue that I could find to save myself. Now I know to dig until I've hit every single hotlink and even gone into their online stores to check "policies." That's key here in this case. They insist their policies are clearly stated on EVERYTHING. But they aren't.
I tried working with Paypal (Visa won't help you if you have a complaint with Paypal) and with eBay. They wanted a lot more info (numbers I had not seen, etc.). I gave up.
I'll get them sold one way or another. My advice is to read, read more, and then read some more. Then send a note to seller with specific questions. Print that all out and have it on the ready if anything goes wrong. I am out over $60 until I can sell this stuff!