I seem to have good luck with people telling me what’s going on. Did she say she’s booking it for herself when she messaged you? Or is she booking it for her parents possibly? I know I have a lot of older people who don’t know how to use Airbnb online so their kids book for them. If I’m uncomfortable with the situation I usually message the person to ask them questions so I understand. If their honest, they should be fine.
I simply explain that we have had some unsavory people in the past and we just want to make sure and keep it a safe and inviting Airbnb. Then I ask what brings them to town.