I saw this with TurboTax Online this year as well! I clicked Pay with My Refund because I was curious about it, and learned that I did not have enough money in my federal return to do it. But then when I clicked through to the payment screen, it said I owed $40 in addition to the $40 payment for federal (I do Delux) and $40 payment for state!
I went back, because there was no way I was going to pay for something I couldn't even use, and the second time I got to the payment screen that charge was gone.
I was really disappointed with TurboTax Online this year... the lack of transparency on what you're paying for which services, and no final amount next to the Pay button.
