The wife and I tried to set up our Amazon store last night. We figured it might be worth it to pay $20/month for two months (for the Pro Merchant subscription) to be able to list some of our stuff there. Worth a shot, at least.
Turns out, some categories are restricted from listing unless you are "pre-approved" by Amazon. Makes it kind of useless for us, as two of the restricted categories are "Beauty" and "Health and personal care", and quite a bit of our stuff would go in those categories.
We ended up talking to customer service and having them cancel our Pro Merchant account for now.
Kind of sucks