HF Tools Heavy Duty 20 Bin Portable Parts (Nuts, Bolts, etc.) Storage Organiser Case with Built-in Carrying Handle by

Why is it $10 more to buy it on amazon prime than straight from harbor freight?

Anyone know where you can get just the bins? I have a lot of these, and love them, but often want more of the smaller bins.

Does the lid open flat ?

Are the removable bins compatible with either the stanley 014725 25-removable compartment professional organizer or stanley's 10 bin version?