Okay so I've had my own ebay account for years sold storage auction stuff as well as occasionally stuff I buy from police auctions, estate sales, going out of business sales, etc.
My problem A. I'm cheap and don't like losing money when customers are idiots and B. I have an ego and when I'm right I'm right and don't like to bend, espeically when people are trying to take advantage of ebay policies or do stupid things.
A while back I started selling on ebay with a partner. He's much more a businessman than I when it comes to customer service plus the money we make is our businesses money which essentially is mine but I don't think about it being mine in the same way as my personal ebay account.
I can kind of take a step back and look at things differently now that its our business and not my personal account. The key to selling on ebay is you have to A. Be willing to bend over and be raped by those pain in hte ass customers, they are few and far between but when it happens you just gotta bite the bullet and do whatever it takes to make them happy and B. you have to lose your ego and leave feedback for people even if htey wont leave it for you, work with people even if they are idiots, etc.
My attitude in the past was always well **** them I'll take a bad feedback I'm not losing money because this guy changed his mind about wanting to buy something or bid on something and never paid. You just have to do whatever to keep people happy and keep your DSR scores high and your feedback perfect otherwise your really just screwing yourself in the long run. You start getting lower DSR scores or bad feedback and you fall lower in your search ranking, have lower selling limits and get cut off before the month is over, etc.