Whether you choose to buy a credit repair book or hire a service, always demand proof that their techniques work. Oftentimes, proof comes in the form of testimonials from satisfied customers, screenshots of removals from credit reports, or even before and after photos of FICO scores. This should be the minimum amount of proof you accept before buying.

I recommend emailing the company and asking for additional proof, if you are so inclined. Not only may they provide you with additional proof, but you also get a feel for what their customer service is like and whether they respond promptly or not.