Kinda ancillary to your point, but if you think the developers who write stuff like this make $100k/year, you've lived in Silicon Valley or NYC for too long. These kinds of projects are typically done by someone making half that somewhere in middle America.
Kinda ancillary to your point, but if you don't know what "fully loaded cost" is, it might behoove you to look it up before assuming it means "salary".
I've never hired a $50k/a engineer, so I don't know what the multiplier is, but I've heard people throw around "2x" as a rough estimate. So you and JoachimSchipper are assuming the same salary, more or less.