One quick test I employ to see what someone values is something I call The Damn Test:
A: ... so yeah, I'll be taking a Google offer sometime this fall.
B: Damn! Congrats man, I'm so happy for you.
A: Haha thanks mate. And what have you been up to?
B: So, I finally got into YCombinator *pause*
A: ... oh nice!
B: and I'm gonna be interviewing for the Thiel Fellowship next week *long pause*
So B finds name brands like YCombinator, Google, and the Thiel Fellowship very impressive. Does that say something about what they care about? These are the hot, shiny collectibles that fit nicely on a resume. This might give you a sense for what motivates the person.