Unlike wondrous items that require GM approval if a player wants to invent something new (because it can become easy to completely break the game otherwise), wands and staves are mostly left to the player to decide what spell(s) to use in their creation.
Then I found some spells with peculiar material components :
- some vary depending on the exact effect the caster wants (beast shape requires a piece of the creature the caster wants to assume the form of) ;
- some vary in gp value depending on the target(s) affected (masterwork transformation depending of the item type, communal nondetection depending on the number of targets) ;
- some are extremly specific and cannot possibly be prepared beforhand (create treasure map requires a piece of the target's dead body) ;
As creating a wand or a staff requires the creator to provide the material components of spells, does it mean that these spells cannot be used to create staves or wands ?