For a coupple of weeks i was on a Deathrun server and they had in there Pointshop under categorys like in the Playermodel category was vip, staff, and regular user and under every category there was the playermodel like only for staff and it was only for staff and i wonder how they make thad? By the way it was this Pointshop http://pointshop.burt0n.net . Need Help and sorry for the Bad english i come from Germany.
A wild guess is a simple gui change to include a dropdown for each rank, a simple if statement to check the items when loaded for a field like ITEM.Allowed. Then spread them out using https://wiki.garrysmod.com/page/Category:DIconLayout List:Add under each sub-category.
Wouldn’t take very long to make.