I was just listening to a podcast that was really interesting.
It talked about how to get into servicing home owner associations. One of the things they talked about was every home owner association has to post somewhere, when they have their monthly meetings.
The suggestion was to find out when these meetings occur and go over to them and stand at the entrance handing out cookies or some kind of treat to everyone that goes in. Ask them if you can make a short presentation about your business or ask them if they have any property maintenance problems you could help them address. It is very important to get to know the board of these groups. Know who they are and let them get to know you. They may not want to talk to you at first, but they might and making that human connection is so very important in ultimately making a sale.
Also find out where the property management offices are in your area and go in there unannounced and visit them. Bring in some snacks. Say hi. Let them know you exist and do this often. Sales will occur when they get comfortable with you and your price is in their acceptable range. People buy from people they know and trust.