Hybrid diapers, how many?

Hana

Hello ladies. I am now enough about cloth diapering to know that I want to sew my own hybrids. The plan is to have a fleece outer layer, cotton inner layer (probably velour or flannel), flannel snap on inserts lined with wicking fabric and cotton velour again.

I would like to have an approximate count of how many to sew, covers and snap in inserts. I want all sizes - newborn to toddler.