In general, in the games I've gmed and played, the players are masters, and their servants are npc's. It actually works out pretty well. I've also played in games where some players are not masters. Each player will be given 150 character points to build their character. My friends and I have a house rule for stats: during character creation, to raise a point in body/mind/soul takes only one point up to rank 6. To raise it to 7 takes 10 points, 8 takes 20, 9 takes 30, 10 takes 40 and so forth, with 12 being the highest rank achievable. After character creation, it costs 10 points up tp rank 7, then it increases as outlined above.
Furthermore, we'll be rolling for summoning order, servant class, and servant. of course, if you want a specific servant, we can discuss that.