Floor Sweep Cost Estimator

Takes a list of listing prices and works out the true cost of buying several, sorting cheapest first because that is the order a sweep fills — taking them as listed would produce a total nobody would ever pay. Marketplace fee, creator royalty and per-purchase gas are all applied, and the headline figure is the average all-in price per item alongside how far above the floor that sits. The floor is what one item costs; sweeping five means walking up the book and paying every cost five times, and the gap between those two numbers is routinely twenty percent or more. A book that climbs steeply across the sweep is flagged separately.