I budded my clones when they were about 4-6 inches tall and they grew mabey 2/3 of that so mabey 8 to 9 inches with about an eigth of bud. It depends on size of plant.
Also, depending on your space restrictions, I would just grow them and just experiment on how high and large you can grow them without burning and crowding each other. Experience is key and knowledge is power.
