"The check is in the mail" has become a big joke for many business owners waiting patiently to be paid by clients and customers.

In recent months, more entrepreneurs are complaining to me that, despite a roaring economy, their biggest clients are paying slower and slower.

Examples I've collected in the past few weeks include a major northern Florida transportation company quietly slowing payments to vendors from 30 to 60 or 90 days, throwing small vendors into a spin; a television network changing its payment policy from 30 to 60 days without notifying vendors; and a giant Texas computer company outsourcing its entire accounts payable department, further isolating itself from upset creditors.

"Most of my bookkeeper's time is trying to get us paid," said the owner of a small Florida-based market research firm, whose largest high-tech client owes him $500,000. "You get a different story from everyone you speak to. Most of the time, you have to start the payment process over and over again."

He asked that his name not be used because he's hoping to be paid in full and keep working for the client, despite the aggravation.

"I add 2 percent to 3 percent interest if an invoice isn't paid in 30 days, but it's a joke," he said. "My client just says, 'Make it due in 45 days.' "

He recently had to sell personal stock to raise $50,000 to meet the payroll and office expenses. His problem is that in order to do the work, he has to pay people up front to review and comment on new computer products and services. He not only pays the participants, but must also pay for the meeting space, the videotaping equipment and travel expenses for his staff, all before his client has paid him a penny.

"Our goal for this market research is to figure out what combination of features would maximize the success of the product in the marketplace," said the owner, who founded his firm in 1983.

Worst of all, his deadbeat client relies on an outside firm to process all payments.

"That company shut downs and doesn't accept e-mail or voicemail several times a week because things are such a mess," said the Florida business owner. "It's so insane."

While most professional consultants refuse to begin work until they receive a partial deposit, he claims he can't because his competitors don't. "If we asked for a deposit, we'd have no business," he contends.

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