But the easiest is probably to use records that are public information. If they work full time they received a W2 from their employers and filed tax returns. That would be the best place to start.
Credit checks are another good way.
Talk to your attorney about establishing this proof. You may have to subpena these documents for a modification hearing. But the easiest is probably to use records that are public information. If they work full time they received a W2 from their employers and filed tax returns. That would be the best place to start.