Hi... I think the best thing would be to notify your local law enforcement and ask that they put on extra patrols in these areas. If you see suspicious activity, I would call and give the exact location and ask for an officer to come out. If you have a neighborhood association, invite the local police to your meeting to express your concerns. You'd be amazed how responsive they can be when they see that citizens are involved in keeping the community safe. On another note, you should see these homes sell eventually, either from a) the builders offering incentives to get folks to buy, or b) if the builder goes out of business and their lender forecloses on those properties and sells them. Hope that helps... have a GREAT day!