While most people (almost 80 percent) have their homes inspected prior to purchase, just who is it that is inspecting the inspector? We've all seen those hidden-camera stories of home inspectors missing major defects, glossing over major problems or finding problems that they then offer to fix (for a charge, of course).

Since the industry isn't closely regulated, it is important to make sure your home inspector is well trained and insured, especially since you are relying on the home inspector's professional assessment to help decide on the biggest investment of your life. To help make sure your professional home inspector is just that— "professional"— the National Institute of Building Inspectors (NIBI), a leading home inspection training organization, offers the following tips to help "inspect your inspector:"

1. Make sure your inspector has proper training and technical support: training in all aspects of home inspection and ongoing support for questions and changes in residential construction techniques and systems
2. Certification: certification by a reputable training institute, which requires re-testing annually, such as the National Institute of Building Inspectors (NIBI)
3. Insurance: insurance coverage, including general liability, worker's compensation and especially E and O (Errors and Omissions) insurance, which is comparable to malpractice insurance. NIBI is the one of the few residential inspection training facilities that requires all its certified members to carry E & O. If you find an inspector who does not carry this type of insurance, it is usually an indication that the inspector has had no formal training, or has a poor track record in the industry.
4. Get a guarantee: a qualified inspector should be willing to provide a written guarantee to back up his inspection findings
5. Avoid a conflict of interest: a professional home inspector should be just that—a home inspector Avoid part-time inspectors who are also contractors, since every home defect found presents an opportunity for them to offer a repair

"If the inspector is missing any of these important credentials—particularly the E and O insurance—don't hire him," warns Joe Tangradi, assistant director of NIBI. "Even if he says he is certified, that does not guarantee that he complies with all these other essential credentials."