Customer Group Catalog

or search frequently asked questions:

Can I set up customer group restrictions by category, product and pricing?
Can a custom block be shown instead of the price?
Can a restricted product/category be accessed via a direct link?
Will the restrict category be hidden on the navigation menu/category filter?
Is it possible to find restricted products via site search?
What if a product belongs to two categories and one of them is restricted?
Can this extension change the price depending on the customer group a user belongs to?