I did the interview when I was looking for a braider.
I think it would be helpful to ask how long they have been styling and to ask to see a book of styles they had done.
I also find that consultations have to be scheduled just like appointments, so you don't want to choose the big paydays for a stylist (Thu-Sat) or after the workday.
Some questions you can answer just by going in, like:
1) Is this place more 'attitude' than quality ?
2) Do they cram as many people in here as possible, ie.
will the stylist give me undivided attention?
3) Does this person care anything about the health of the hair or just getting the style I asked for?
4) Will I have to spend a good part of my life here or can the service be performed in a timely manner?
5) Will the stylist explain what he/she is doing and give me instructions on how to maintain the style or is everything a deep dark secret.
6) Does the stylist understand the difference between the terms: hair cut, hair trim, snipping the ends ?