Need some more help as I don't think the normal faction plugin can do this, but if it can sorry! I'm going to have 3 sort-of 'groups' in my faction server. Each one giving the player different items and the like but I'm not too sure how to do this. I want to have people who can join a group, get given a certain kit, and then create a faction within that group so you can have rivals. Hope this isn't too confusing and thanks in advance!
It's pretty self explanatory, you just assign the upper "factions" to a group made with GroupManager. Then within these groups, use Factions to divide the players.
Whatever works out the best for what you have in mind, really. A little messing around with certain plugins can do miracles.