I've been on streaming so long that the shelf of Blu-rays behind me had turned into furniture. The keepers stayed, and I decided to sell the rest. Selling a few hundred discs one at a time is its own part-time job, so I built a little tool to do the boring parts: scan every barcode, look up what each disc is, figure out the handful worth selling alone, bundle the rest into themed lots, price them, and spit out eBay listing sheets. Here's what it does, and the one pricing lesson that changed how the whole thing works.