You’re legally required to get a building permit for any significant construction project. That allows building officials to visit the site periodically to confirm that the work meets safety codes.

On small interior jobs, an unlicensed contractor may try to skirt the rule by telling you that authorities won’t notice. On large jobs that can’t be hidden, the contractor may try another strategy and ask you to apply for a homeowner’s permit, an option available to do-it-yourselfers.

But taking out your own permit for a contractor job means lying to authorities about who’s doing the work. And it makes you responsible for monitoring all the inspections—since the contractor doesn’t answer to the inspector, you do.

How to protect yourself: Always demand that the contractor get a building permit. Yes, it informs the local tax assessor about your upgrade, but it weeds out unlicensed contractors and gives you the added protection of an independent assessment of the work.