From last release in hercules was added new shop type: expanded barter shop.
This shop allow buy item with different amount and pay with other items or with money. For removed items supported refine levels.
Also this shop allow infinite or limited numbers in shop. Limited numbers saved into database.
For use shop example script uncomment in file npc/scripts_custom.conf this line:
//"npc/custom/expandedbartershop.txt",
This shop supported from clients:
Rag