Hmmm, well... Human beings in GURPS are fairly simple. There really isn't that much work needing to be done but things can get tricky when you are trying to stat out a child or young teen character, as was a huge part in most of The Lost Boys movies.
I know to all looks complicated and scary for people who've never played, but it's really not.
Most of this is To Be Written
I try to limit NPCs and Secondary Characters to about 50/60 points, while Main Characters and Vampire Hunters get 100/150 points based on experience. For example, Alan as a teenager hunter gets 100 points while an adult Alan would get 150.