Homes with solar panels sell faster and for higher prices according to a 2008 study. Through a program, solar panels can be installed on listed homes at no cost to the seller. Buyers then receive a 30% federal tax credit of around $12,000 on average, as well as a state rebate check for 10-15% of the system cost within 90 days. With solar, the monthly electric bill is replaced with a statement showing energy produced and used, resulting in an average end-of-year bill of only $7.50. This can lead to more sales and referrals for realtors.