It's been a while, but what I remember from my GA interviews were:
If you have an ETA of xxx and you have a tempo till xxx, how much holding fuel do you need?
What's your VFR met mins?
What would you do if you realised you wouldn't make it back before last light in a single engine with pax?
MTOW of current a/c being flown?
What do you know about us?
Why do you want to work for us?
5 year plan? (Be honest, every GA operator knows you don't want to stay there for life so don't BS them)
Tell us about yourself
A time you've had to make a decision on the spot that may not be popular?
Ever had to deal with difficult pax?
Have you had to refuel from drums? Do you know how to remove seats etc.
That's all I can remember, hope it's helps to give you a bit of an understanding