But what happens after you receive your parts from a Web-based supplier that isn't an authorized distributor and discover that the parts are defective or not genuine? Can you return the parts?

Distributors want you to believe that one of the most important values that authorized or franchised distributors offer is warranty protection; you don't have to wonder whether the parts are genuine.

On the flip side, nonfranchised or independent distributors say component quality levels are so high that it is rare they get returns, and they're willing to take the risk. Nonetheless, some offer only 30-day return policies in their product guarantees. But most reputable ones will eat the return.

As for online auctions, engineers should be reluctant to participate in them. Make sure the online auction site offers a quality guarantee or a standard warranty for all parts.

Read the fine print in the terms and agreements at the online site before you sign up. That way, you'll know exactly where you stand when something goes awry.

Since many Web-based distributors are not franchised to sell the parts, they don't offer manufacturers' warranties. Some provide their own one-year warranties; others may have disclaimers that they are not held accountable for any warranties. Then there are those that offer product guarantees. Make sure that you're clear on exactly what their return policies are because no one wants to get stuck with parts they can't use.

It all boils down to whether the company is reputable. Ask the online vendor the same questions that you would ask an independent distributor or brokerage house before ordering. How financially stable is the company? How has it handled product returns in the past? Are the terms of the warranty or guarantee comparable to the manufacturer's warranty?

The bottom line is to know your online supplier before you make any commitments.