Staff in D&D 5e costs 5 gp, weighs 4 lb..
An arcane focus is a special item--an orb, a crystal, a rod, a specially constructed staff, a wand-like length of wood, or some similar item--designed to channel the power of arcane spells. A sorcerer, warlock, or wizard can use such an item as a spellcasting focus.
Frequently Asked Questions
The Staff costs 5 gp in D&D 5th Edition.
The Staff weighs 4 pounds in D&D 5th Edition.