First of all, eBay buyers are 100 times more important than their sellers. However, you also have to understand that the actual eBay employees are not the sharpest tools in the shed. First, if you are a legitimate business (sorry weekend sellers) you can get a court order against eBay AND the seller claiming defamation and list several ways that negative feedback makes a negative impact on your business (and believe me, it can cripple your online business). It is very easy to get this order, took me about 15 minutes once I explained the situation in basic real-world terms and comparisons. Send in a certified piece of mail, something with lime green tape around the edges or something, something really obnoxious that stands out to eBay AND the buyer. As soon as your buyer gets the item (you get confirmation from your carrier) Call them up, and tell them to get on Google and type in "eBay defamation" which brings up a video of a guy who was successfully sued for like $15,000 for leaving neg. feedback on some old clock or something. Casually explain how their negative feedback can really hurt your business, but it can be repair. Offer to refund the item, or whatever you need to do. Give them links on how They can e-mail eBay support and explain to them that they made an error. Do not send a "Revision Request" you only get like 6 for every 1000 transactions, and most are ignored as they look like spam to buyers. It can and will be either removed, or left a positive. If your buyer is still being a total a'hole, have no fear. eBay is incompetent and will jump at removing the feedback within 2-3 weeks from the time of mail confirmation. Call them and tell them you spoke to the buyer and they wish to remove it (even if they didn't agree at all) and if eBay fails to do so, you will sue them, and that you have already sent them a court order CERTIFIED MAIL and that you have proof that it was received. You must remain calm and serious. eBay will delete it.
Worst case scenario is:
You call the buyer and be like "Look, you aren't happy with me on eBay, and I agree that I messed up. I would really like that feedback removed because I'm:
Selling my kids' video games for his money in college and nobody will buy from me with a neg.
Need the money for bills as I'm unemployed, very sick, injured, etc and need the money because nobody will buy from me
Because you used your wife/husbands account and if they find out you got them a neg, that will be really pissed off (housewives Love this one, I use my girlfriend)
and that if they remove the negative feedback and leave you a pos you will:
Send them a $50 Red Lobster/Olive Garden/Toys R Us/Walmart/Best Buy Gift Card
or..
$25 when you get paid next tuesday, and you will pay through PayPal
So... the buyer leaves you a positive, even if you have to do a revision request.
Then you send them the $25, and a $50 gift card... NOT! Don't be stupid, that person was willing to kill your online source of income, almost like taking the bottle out of your kids' mouth, or walking into your home and stealing everything from your fridge, for no damn reason whatsoever. You will send them ABSOLUTELY NOTHING. They will call you probably, ignore them, tell them you are going to mail it, then say I might got lost in the mail, or tell them to go F themselves.
eBay feedback is serious business. Screw eBay for putting so much power in even the most newbie eBay buyers.