FREE demos is always the best way to market your business. All it takes is talking to the right person to set up a demo. Once you display your cleaning abilities it's almost always a close. People are amazed by roof cleaning. For commercial roof cleanings you need to talk mostly with diectors of facility maintainance. A cleaned this roof for FREE for a retirement community in November, now I'm going out there in May to clean about 30,000 sq. ft. of roof. This is the second community I've landed this way. The other is on a bi-monthly cleaning contract. Hardest part is getting the demo set up. Just be persistant and the hard work will pay off.