Watch out for companies that ask for money up front. The FTC found this practice to be harmful and outlawed it. Those who still collect money upfront are violating the law or using loopholes to evade the law.
Before trusting a debt settlement company, be sure to ask for references and check out their background with your state attorney general's office and the Better Business Bureau. Remember: no one can guarantee to eliminate your debt, so be wary of claims that sound too good to be true.
This video produced by the Federal Trade Commission describes what you can do when collectors go too far: