I want to show an interactive map similar to this one As you can see, each property is roughly outlined here. I was wondering if there is a free or paid service that I can use to show this? I would be working with javascript to do this.
Well, I don't know exactly how this is done, but normally you would tap into the official property records (if they're available online), to create outlines for properties based on map coordinates. If there is something like that available, either via an API, or just as overlays you can cut up yourself, then at least you're somewhat closer to reaching your goal.