Air compressor dealers usually specialize in one brand - often, manufacturers require exclusivity from their dealers. The result is, you'll have to talk to a few different dealers to evaluate multiple brands. On the other hand, because the dealers are forced to specialize, they develop a good understanding of the manufacturer's wide range of offerings and can usually do a very good job of supplying you with the right compressor for your needs.

In your research, be careful not to get overwhelmed with specifications and product claims. When buyers feel like they have too much information, they often wind up basing their purchase decision only on price, which is never a good idea. Take the time to talk to each dealer and understand which compressor is right for you - you'll be far happier in the long run with the right compressor than you will be with saving $500.

Here are few characteristics to consider when comparing dealers:

Longevity. How long as the dealer been in business? A dealer that's been selling air compressors for 15 or 20 years is obviously doing something right, and is more likely to be around in the future to support your purchase than one that is just entering the market.

Dedication to compressors. Some dealers choose to offer a few air compressors simply as a convenience to their customers, even if the bulk of their business is in tools or supplies. If air compressors are the dealer's main business, they're likely to have a better understanding of the systems.

Strength of manufacturer. Most compressor manufacturers are well-established companies, but you should still check their commitment to the business. Some heavy equipment makers might make a small handful of compressors but not really focus on them - stick with those that sell a full line of air compressors.

Staffing. Does the dealer have enough support and maintenance staff to protect and service your investment? Are they well-trained and experienced?

Service rates. How much will you have to pay for repairs? Will they sell you a maintenance contract if you want one, or just sell you parts and let you do the work yourself if you prefer?

We also recommend that you ask potential dealers for references. Of course they'll supply you with references who are happy with them overall, but by asking the right questions, you can get some good information. Ask about how often their compressor needs repairs and how prompt the dealer is to make them. Ask if they've purchased additional compressors, and if they bought them from the same source. And ask leading questions such as, "What could this dealer stand to improve about their operation?"

Of course a reference from someone you know is even more valuable than a reference the dealer provides. Talk to your industry contacts about their air compressors - find out what they like and don't like about their compressor and their dealer. That information can make a big difference in your purchasing decision.