We know that there will be 4 epilogues, one for each route. Within each epilogue, though, I suspect there will be multiple endings, depending on choices that were made during the game. There could easily be a dozen or more possible endings (good, bad, and so-so) to this game.
In that way, I can see 8 at best. Sandra, Adriana, Lisa, Haley solo, within these, 2 branch, Haley plus and Haley minus, depending on your points with her. Small stuff like whether you dealt with Klaus or not won't matter, since that was just a plus option to vent, the most it will get is a sidenote, if it gets mentioned at all. Other than that, Diane and Alana were phased out of the story already, and the parent reaction might be dependent on the Haley rp as well, but since there were not any genuine variables for them, it won't be big enough to make a new branch.