If you have a beat or already recorded stems, you can text or email them to me ahead of time or bring them to the session. WAV files preferred, but mp3 is ok

Typically no, I mix & master outside of the session but if this is preferred then I can certainly mix with you

Depends on the length of the song, number of tracks, amount of editing required etc but usually anywhere from 1 to 3 hours per song

The initial mix of a song will take a week at most, with revisions being done within a few days