Keep in mind that along with the community-based reputation of feedback, you are building direct relationships with individuals. Someone who buys one thing from you may well be interested in bidding in other auctions of yours. In the description, tell how you acquired the object. Be chatty and friendly as well as accurate and informative. Then include friendly questions and comments in your correspondence about payment and shipping. By so doing, you can uncover what else they are looking for and why they collect what they collect. I've done many deals offline with eBay customers, based on their interests. You can also get clues as to how to better group, organize, and describe what you have to sell at eBay. For instance, selling bottle caps -- what is the optimum number of caps to have in an auction lot and should they be mixed (many different kinds) or all of the same kind?

If you have many items that fall into the same general category, over time you develop your own niche -- establishing a reputation in that sub-community at eBay and perfecting your descriptions and email messages, based on what you've learned from your previous auctions and related correspondence.

Another side effect of selling at Ebay is the people you meet. For instance, someone who bought a Wild Bill Hickok comic book from me had just sold a script to a TV network for a pilot for a series set in Deadwood. Someone else bought an old copy of Playboy because there was an Elvis Presley poster inside. The buyer is an avid fan, who legally changed her name to "Presley", bought a house next to Graceland, and moved there from New Jersey. She now makes a living selling Elvis-related memorabilia.