Generator installation costs in Lewisville typically range from $4,000 to $15,000, depending on the size of your home and how much power you need. A smaller 10-14 kW system for essential circuits runs $4,000-$8,000, while whole-home systems for larger properties can reach $15,000 or more.The total price includes the generator unit, automatic transfer switch, installation labor, permits, and any necessary electrical panel upgrades. Natural gas line installation adds $500-$1,500 depending on the distance from your meter. Carroll Service Company provides upfront pricing before any work begins, so you’ll know exactly what to expect with no surprise charges.