The girls who interviewed me did not seem to have a list of questions. They mostly talked about Habitat for Humanity and what the person hired would do in this particular role, and then would just ask me something like, "What do you think about doing that?" or "How would you feel about ___?" There were not any difficult questions, and I did not have many opportunities to speak, as most of the time was spent with the two girls explaining things that I had already read about on the website and in the job description.
I had read about other interviews on Glassdoor and felt what was said about interviewing for Habitat was pretty accurate to my experience.