If installed correctly, a solar energy system should last 40 to 50 years. That’s why a key aspect of switching to solar is finding a qualified contractor to handle the job—one that has the right knowledge and experience and is committed to customer satisfaction. Here are a few attributes you should look for in a solar contractor:

Longevity and legal credentials

Find out how long the company has been in business—this is a marker of both experience and customer satisfaction (it’s hard to stay in business if your customers aren’t happy). Also, make sure it’s fully licensed and insured (including workers’ compensation).

Detail-oriented

A solar contractor’s job proposal should contain a full breakdown of labor and materials costs, including a list of the products to be used. This shows that the contractor pays attention to detail, which is a crucial attribute when it comes to solar installation. In contrast, an over-simplified proposal should be a red flag that the contractor may lack diligence—or worse, is intentionally withholding information in order to take shortcuts or provide sub-par products and materials.

Willing (and able) to answer questions

A good solar contractor will be forthright in answering any questions you have about the project. They should be able to provide a thorough explanation of the installation process, including how the system will be attached to your roof. Keep in mind that the condition of your roof is important, so the contractor should inspect it beforehand.

Committed to quality

One problem facing the solar industry today is contractors that aren’t upfront about the quality of the products they use. They’ll sell wattage to a customer and then use any product that’s available to fulfill the contract—even an inferior one from a second-rate manufacturer. However, to ensure your solar installation is protected for the next 25 to 50 years, it’s important to buy from an established, reputable manufacturer that will be there to back up their warranty when it’s needed. Ask your contractor what product brands they use and do some research to verify their quality.