A little context goes a long way.
Three worked examples for the decisions behind the tools.
Keep SKU leading zeros when checking a CSV
Understand why 00123 and 123 are different identifiers, spot whitespace and case collisions, and inspect a CSV without rewriting the original.
Spot a price increase hidden by a smaller pack
Compare supplier quotes by unit cost, not pack price, and handle ambiguous SKUs and zero-price percentages explicitly.
Calculate discount break-even with payment fees
A worked bundle example showing percentage fees, per-order shipping, contribution profit, margin and the correct price floor.