I always print the passenger list for the bus heading to the IRS and the acknowledgements report when the IRS tells me everybody got there and cleared their inspection.  I keep those all together in an expandable folder for the year.  I follow that up going into the "accepted" tab and print the client history showing acceptance and I put that into the client file along with the 8879.  Not that I don't trust Intuit or the IRS .................. but I don't really trust Intuit or the IRS and like proof of what I did .................. just in case.