I wonder if there is some way to transfer into "engineering" terms how the finances are???? Sometimes putting things into the terms that we do understand easier makes other things easier too.
I can imagine how frustrating it can all be....but perna is right, he's not doing it to upset you...he really has a problem understanding money. Good thing he didn't go into accounting!
Hope you can find something to help him understand. Best of luck to you all!
Hugsss
sabby