The American Libraries Association (ALA) recently had a form to ask for questions to ask during interviews and has proved to be a valuable resource, you can see their responses here.
I figured a GIS version might also be a good resource, and using Google Forms and Sheets as well, I have made a version for GIS professionals, it has questions for the interviewers to ask the candidate and candidate to ask the interviewers. It was originally posted in The Spatial Community, a GIS oriented Slack group made up of GIS users and developers, so most of the responses are from there as of writing.
Fill out the form here.
See the responses to the form here.