Page 90-91 of Dangerous Covenants has a chart describing the expected pay-scale that the various Hired Gun specializations can expect for handling various jobs. It's the first time that we've had some close-to-specific guidelines on actual monetary rewards relative to an adventure. Enter the Unknown didn't have this, and I don't expect it to be the norm in the other sourcebooks as they come out.
I think the most helpful info is that the per-person rate per hire works out to be 500-2000 credits, depending on the nature of the job and the adventure itself. It also gives some guidelines (Average vs. Specialist) as to how much more one can be expected to be paid for when players get to higher skill levels. A group hire ranges from six to twenty thousand... which could serve as a general guideline for monetary rewards in a given campaign. Of course, alternate rewards are also good, but this is very helpful.
There's a lot in the book, as discussed elsewhere, but I think this deserves special attention.