You can configure which property details show up when you click on a property in the map. Learn more by reading about popovers.
To change the value shown when you hover over a pin (before you click on it), edit the field "gm_MapData" in your properties table and change the field used in position two, after the comment "Marker Data: Position 1 - 5" Whatever is in position two will be used in the tool tip. Don't forget that you'll need to refresh the map after making changes to this field.
In addition to just working on the main layouts, some of the other things you may want to change are in scripts or configured on their own layouts.
See Icons and Pins
See Area Outlines