How many Diapers?

Jamie • We have a 12 year old boy, 10 year old girl, 11 month old twin boys and 1 month old twin girls.
Im due with my twins in 8 weeks and I'm stocking up on some diapers. What would some of you recommend as far as how many per size I should get. Should I get a couple premie or just stick to newborn? And how many newborn packages would be good?