For most homeowners, a full residential solar setup, panels, inverters, mounting hardware, permitting, and professional installation, runs between $15,000 and $30,000 before incentives. Your actual cost depends on your home's energy needs, roof characteristics, location and other factors, all of which we'll break down in. System purchases offer dramatic savings: Buying panels as part of a complete solar system costs 40-65% less per panel ($0. 50/watt) compared to individual retail purchases ($0. This typically translates to about $2. 50 per watt of installed capacity (more on price per watt below). The total price depends. Total cost depends on everything from the type of panel to the size of the system to the complexity of the installation.