If you do a substantial amount of selling on eBay and would like to get a better feeling for how you're doing (and how to improve it), building reports with Ruby-on-Rails can help. This article explains how. It is excerpted from chapter 6 of the book Practical Reporting with Ruby and Rails, written by David Berube (Apress; ISBN: 1590599330).
Essentially, business is about money changing hands, and for that to happen, you need to have a buyer and a seller who need to connect somehow. Where they connect, of course, is a marketplace. Marketplaces come in many varieties, from a high-profile diamond market in London to a corner flea market in Wyoming. Of course, most businesses choose their marketplace according to the ability to reach their customers. eBay is perhaps the world's largest marketplace for many types of goods.
Unfortunately, it's not enough to simply sell your product on eBay. You need to intelligently price, describe, and promote it. This requires experimentation with all of the possible factors, as well as the ability to analyze which tactics increase sale price and volume. You also need to assess how cost efficient each factor is, since some factors are not free. For example, eBay allows sellers to place small icons next to a listing or to boldface the listing's title for a small fee. For a much larger fee, you can place your listing in a special "featured items" category, which appears at the top of every search. Any of these options may or may not be appropriate, and reporting can help you decide which options to use.
Of course, there are many other reasons why you might want to produce reports based on your eBay-driven initiatives. For example, you may have hired an intern to list a certain number of items per day, and you want to ensure that the intern is actually doing her job. Or you may not choose to sell on eBay at all, but rather want to make sure that no competitor is selling inferior goods on eBay and claiming they are yours.
Fortunately, the work of creating eBay reports does not have to be done by hand, as You'll learn in this chapter.