Besides the basic demographic questions of age, sex, homeowner, etc., ask them about their current buying habits regarding similar sefvices.
• Where do they presently shop for these services?
• What's the most and average price they pay?
• What is most import as far as features and benefits?
• How did they hear about these services, i.e. TV, newspaper?
• Do they use coupons, the Internet, direct mailers?
• What would they like to see the service do better?
• What about warranties?
• Do they use a credit card?
• Do they shop online?
That should be enough to get you started. Good luck.