HI @CrystalWind,
This depends on how you setup your multistore?
Out of the box Magento magento supports what you want, if you setup the multi-stores as websites, so in this way you retailers have their login and end-users have theirs.
Catalog/products can be shared across these sites.
You could face a challenge with the pricing, if this has to be 100% unique per store, I think a module/extension is needed.
Let me know if you have any questions.
-- Best regards --
Kent Christiansen | Magento Certified Solution Specialist