Decide whether you need a single stage or two stage snowblower. Single stage snowblowers use one piece of equipment to move the snow to the center of the machine and discharge it. They're lightweight and best for areas with light to moderate snowfall. Two stage snowblowers use one piece of equipment to break up the snow and a separate piece of equipment to discharge it. Two stage snowblowers are better equipped to handle heavy snowfall.
Select a name brand model. Used snowblowers are more likely than new snowblowers to need spare parts and repairs. Name brand models, such as Honda, Toro, John Deere or Craftsman, have more readily available replacement parts.
Ensure that the snowblower doesn't have numbers or letters stenciled on it. Stenciled numbers or letters generally indicate that the machine was part of a commercial or rental fleet and has probably been used more than a residential machine.
Verify that the belts and auger, or rotating shaft, are in good condition and that there's no rust on the machine.
Find out if the safety switches work. Snowblowers have moving parts that can cause serious injuries so you should never overlook safety.