10. May I see a work in progress?
Depending on the nature of your project, it might be helpful to visit an electrician's current job, for a behind-the-scenes look at his work. In general, you're looking for evidence of orderly, methodical installation: neat cable runs near the service panel (breaker box), clear labeling of circuit breakers, regular anchoring of cables, switch boxes that sit squarely and finish flush to the drywall surface, etc.
Like a plumber, doctor and auto mechanic, a trusted electrician is a valuable member of a household maintenance team. As you cover your list of electrician questions, listen for a panel-side manner; you want someone who explains what he's doing and why, and who will help you understand the essentials of your system (or as much as you care to know). Ideally, the electrician you hire now will be a good source to call for emergencies and other projects down the road.