The Better Business Bureau (BBB) is urging contractors in Missouri, Illinois and across the nation to be alert for telephone solicitors trying to convince them to sign up for an online program offering free job leads.

Several contractors report that after paying a $99 "background screening fee," they got no work and often were unable to contact anyone with the company that called them.

In its notice, the BBB said contractors need to use "caution when dealing with Construction Crews (constructioncrews.net), Contractor Support Management (contractorsupportonline.com), Commercial Crews (commercialcrews.com), or any of several other construction lead companies requiring upfront fees to screen prospective contractors."

It seems so far that the companies doing the scamming are based in California, the BBB said.

"Contractor Support Management, of North Hollywood, Calif., has an 'F' grade with the BBB, the lowest grade possible. It has received more than 100 complaints, the vast majority from contractors who said they received nothing for their money," the BBB said in its advisory.

Anyone approached with a solicitation like those described can contact the Better Business Bureau to get a review of the solicitor.