Energy efficiency and sustainable home features may have seemed trendy a couple of decades ago, but now they're becoming must-haves for today's buyers. Two REALTORS® who have built their businesses in green real estate—Jan Green, an EcoBroker in Scottsdale, Ariz., and Christopher Matos-Rogers, founder of the sustainability-focused Matos-Rogers Group in Atlanta—share steps they took to break into the sustainability market, how green homes are changing and what other pros need to know about rising demand for these properties.