Alternatives
PCB DFM tool alternatives guides
A free fab-side DFM check is enough for many boards. This page says when, and where MakeIRL’s paid KiCad preflight is the wrong choice.
When a free gerber check is not the job, the paid gate is the KiCad project itself: schematic ERC, DRC, schematic-to-PCB parity, and BOM lines checked against live distributor stock.