Competent dealers of commercial generators can make a big difference in your overall satisfaction with your backup power system. You'll need understandable answers to complicated questions - look for a dealer who is knowledgeable and dedicated to generator sales and service and has been for a while. Large industrial or construction equipment dealers who happen to sell generators as a side business may offer a good price - but they won't have the expertise of a dealer who's more dedicated to selling and servicing commercial generators.

Because maintenance and service are so important, you'll most often want a generator dealer in your local area. A more distant dealership can sometimes connect you with licensed service technicians who are in your area, which can be okay but is generally not the preferred arrangement.

Ask what maintenance services they'll provide. At a minimum, a standby generator requires an annual checkup of oil levels, air flow, and other factors.

Other questions to ask:

• How many technicians do they have? How many trucks?
• How long have they been in business?
• How many commercial generators similar to yours have they installed in the last year?
• Which brands do they work with the most?
• How long have they carried the brand you're interested in?