Yes it depends on which aircraft you want and where you want to be based. Up north you don't make as much as you will if you fly out of south Texas. Falcon 20 FO pulls around 5-6k a month.

You get a base salary of (don't hold me to this) $27k.
You get paid if you help load the planes.
You get $125 evertime you cross the boarder.
You get .12 cents per mile.

Couple the mileage with the border crossing pay and that's why the guys in Texas pull so much ahead. They also have a 727 but don't need anyone to fly it just yet.

You will have to live in your base and have a 30 minute callout to be at the airport when in the south. They are not CASS.

They have a few Convairs they fly up north but I don't know their pay. I think 13 or 14 cents per mile but they are much slower.

Currently they aren't really hiring. That changes often though. Captains make in the 6 figures down south. Much less up north.