Items in combat
What's an adventurer without useful crap? Ammunition, magic salves and potions, enchanted objects, and adventuring gear are all things characters can have on their person and want to pull out and use during combat.
Retrieving an item from a handy location, such as a belt pouch or a bandoleer, takes 1 AP. An inconvenient location, such as a backpack, takes 3 AP. Having to take the pack off and dig through it would take 6 AP or more. Pulling arrows from a quiver takes no time at all and is figured into the AP required for using a bow. If, however, one had extra ammunition in a place that isn't immediately available, it would take AP to retrieve it.
Using a consumable item (quaffing an elixir, dropping a smoke grenade, etc.) will generally take 1 AP. Some items may take longer to use and it will be noted in their descriptions.
As a general rule, activating a supernatural or magic object takes 4 AP unless noted in the item's description.