If it’s been a while since you’ve looked at your credit report, you may be surprised to find errors, mistakes, or even a black mark or two. Fortunately, a Credit Repair Company can help you fix those mistakes and erase those black marks. Watch out for scammers, though, and choose a reputable Credit Repair Company with these tips:

Don’t pay anything up-front

Avoid a Credit Repair Company that wants you to hand over a fee or payment before they meet with you. Reputable companies will first talk to you, assess your credit report and discuss your current situation before asking for any type of payment for their services. An up-front fee is a red flag that the company will probably take your money and run. And no matter what type of charges you may incur, be sure they aren’t exorbitant. If a Credit Repair Company claims your case will cost thousands of dollars, look for another one.

Watch out for “re-inventors”

Some companies will tell you that you can wipe your credit slate clean by “re-inventing” yourself with a new social security number. But that’s not true! In most cases, what they plan to do is get you a new credit report by applying for an Employee Identification Number (EIN)–used by businesses–which resembles a social security number, and you’re told to use it as such. But this practice, known as “file segregation,” is a scam, and it’s also illegal! Avoid any Credit Repair Company that suggests this practice.

Look for one that helps you help yourself

A good Credit Repair Company will tell you (for free!) what you can do yourself, such as writing letters to creditors and contacting the credit reporting bureaus about errors. Avoid any Credit Repair Company that encourages you to do anything illegal or unethical–such as disputing a legitimate charge or fee on your credit report.

Before signing up with any Credit Repair Company, make sure you check with the Better Business Bureau. They’ll have records of any formal complaints against the company, so you can avoid scammers and rip-off artists.