According to the EnergySage Solar Marketplace study, a solar panel's design and construction cost about 10 % of the total cost. If you mount the panel yourself, you can theoretically save a lot of money. A skilled artisan may build and install a solar panel, but it is often recommended that a licensed professional be employed. The solar system has been in service for about 25-30 years, so you must understand the initial expense and relative benefits. If you buy the material and mount the panel on your own, it will cost you less, but consistency will be compromised.  The material available online will not be of the same standard as licensed solar panels with 20-25 years of warranty.