Item in question: Huggies Snug & Dry diapers, size 4
Costco pricing: 200 diapers on sale for $43.99 (comes out to $0.22 per diaper).
Buying at Costco means a trip to the store as well.
Amazon pricing: 140 diapers on sale for $23.51 (comes out to $0.17 per diaper).
Remember, to get this special pricing, sign up first for Amazon Mom. Then select the Subscribe & Save option on the diaper's product page. Two-day shipping is totally free as a member of Amazon Mom. (Please note that if you use my link to the diapers and end up purchasing them, I get a small percentage of that sale!)