wow!
i just wrapped up two songs, that i started recording 4 years ago!!
the biggest pain in the ass is
>>>>TIME >>>>>>>> = 0. for me, the way it usually works is, i steal away an hour here, a couple there...
and on rare occassion, i might get an entire 4-5 hour session in...
so, when i do that, like i did this past friday and saturday, i focus on one element..
in this case, vocals.
i knocked out two songs, with a total of 22 tracks of leads and harmonies, in about 8 hrs total.
mixed, trimmed and tailed, etc....
so, back to the answer, it would be hard for me to ever come up with a realistic amount of time for a given song.
i HAVE done an entire song in a single day, tracking wise...
the "Bats Brew (melange de la chauve souris)" song, was tracked in a day, not counting the drum tracks, which i did not record.
i also used a shure sm57 for every track (sans drums) on that song, so it was the benchmark of simplicity for me.
song example link:
https://app.box.com/s/6bmrm4beelhjuftdwb9z