Most comparisons between fulfillment partners stop at the rate card. The things that decide what your customers experience rarely appear on one.
1. When is today's cut-off?
A 2pm cut-off and a 5pm cut-off sound alike. Those three hours decide whether an afternoon order ships today or waits a day.
2. How is stock recounted?
Ask how often the shelves are reconciled against the system, and who absorbs the difference when they disagree.
3. What happens when a return arrives?
Returns stacked in a corner are capital that has stopped working. Find out how long it takes for a returned item to become sellable stock again.
4. Who do you call when something breaks?
One name and one number is worth more than a tidy portal nobody is watching.
5. Can this double next month?
If the answer involves a new contract, you will be negotiating it during your busiest week of the year.