No seat motors, though we do have the flexible shafts. Also - worried about the durability of the plastic gearboxes, some of them had damaged out of the box.

Are there seat motors - I see seat motor flex shafts - but I don't have them and I don't see them on the latest parts list.

So if this is right all the supplied motors require PWMs except the window motors.
So you should only need 7 PWMs if you use every legal motor.