Blood is complicated. The general rule for it is please don't, not unless it's something to do with that specific person. You generally don't want parts of people's bodies getting mixed in with your magic. Which- probably also true for baking cakes, I suppose.

[ Not that that has ever once stopped him. But Belmont blood is a pretty specific component in itself. ]

Grave dirt, for vampires. You can use it to replace the sand, else mix it with water and make the written component with mud. Generally don't need the specific components for that, though. Belmont and all. Vampire bullshit comes naturally. Fishmeal for werewolves. Whole fucking list of different components for mages, though most of them are better to track the magic than the mage themselves.