In 1983 the Better Business Bureau (BBB) logged 85,700 complaints nationally alleging mistreatment by mail- and phone-order businesses. By 1992 the number had shrunk to 22,680 -- a trickle, considering a parallel surge in direct-sale revenues.

How to explain the divergence? "The industry is learning to market better," observes Lorna Christie, head of consumer affairs for the Direct Marketing Association (DMA), the industry's trade organization. "Mail-order computer companies know they need repeat sales to survive, and that requires hassle-free buying. So everyone is making customer service a priority." And the lack of hassles is paying off: from 1990 through 1992, mail-order sales of computer products rose, roughly, from $3 billion to $7.5 billion.

But, Christie admits, direct buying isn't risk-free yet. Hence these tips:

Before ordering, check out the seller through its local BBB. A history of slow delivery suggests financial difficulties and may augur bankruptcy.

Study customer-satisfaction provisions. The price might be right, but warranty terms can be costly (example: a "restocking fee" for returned goods).

Keep a detailed record of your order. Save correspondence and canceled checks.

If you can't settle a beef, report it to the publication that carried the ad. Many publishers will pursue a claim on the complainant's behalf.

Bring the problem to the DMA. Its Mail Order Action Line (MOAL) intervenes in disputes and, given the pressure 3,600 members bring to bear on an offending merchant, the customer usually comes out on top. MOAL's success rate is approaching 80%. Mail a summary of the situation, along with photocopies of pertinent documents, to Mail Order Hot Line, Direct Marketing Association, 6 East 43d St., New York, NY 10017-4646. (Don't phone; you'll only be told to put it in the mail.) -- Robert A. Mamis

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