[carbonmachine]

> I understand it could require swapping the platters into a working drive, but I don't imagine that being such a costly procedure.

It may need to be performed in a clean room, which is likely expensive to set up and maintain. Perhaps it's the required equipment that drives up the cost?

I've wondered if data recovery shops distribute the cost of the intensive recoveries (e.g. swapping plates) across the smaller gigs (corrupt file systems and other stuff).