Where can I see total or available cash flow? If I make a coach offer that is too high, it doesn't tell me how much too high it is.

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Jon, I went ahead and figured it out with a binary search (some people might call it a "phone book search").

You can see it on your contract offer page, although there's not a total displayed there, but the black part of the bar is what you have left. I do have a pending update that gives a little more information there and makes it a bit clearer.