[fooker]

The fuel costs about half a million.

Beyond that it's mostly people's times and materials they have stockpiled for economies of scale.

I would guess the lost satellites cost a bit more to manufacture that to launch in a reused Falcon 9.

[elihu]

Don't they waste the upper stage on Falcon 9 launches? (That being one of the reasons they want to transition to using Starship.)

[6nf]

The fairings alone add another million. The whole upper stage is not re-used at all.

[onethought]

They recover the fairings.