The GND included universal healthcare and jobs programs, both of which are the biggest line items in the AAF estimates. They estimated the cost of dealing with carbon emissions at around $7 trillion. And that money is largely for capital expenditures, which anyone who has half a brain would finance over 20-30 year period. And a large chunk of that $7 trillion can be passed off to utility rate payers over that time period with barely a noticeable increase in rates based on how cheap renewables are getting.
Also, AAF can hardly be trusted to fairly evaluate the cost/benefits. A slight increase in utility bills pales in comparison to having to abandon your house due to increased flooding due to climate change. It is funny how when they are doing analysis of tax cuts, they turn over every stone looking to squeeze out questionable "economic productivity" increases to add to their models, and yet when it comes to climate change, they just throw out a bunch of big numbers and call it a day.