Trigger "Place pin from address" (I'm assuming this uses PHP and not JS) on the save_post hook. Then do a loop of all property posts and run wp_update_post on each (which will fire the save_post hook).
If the place pin from address is using JS then you'll need to replicate that functionality in PHP to use the above method. There's a class that will help you do just that.
Useful links:
https://github.com/jstayton/GoogleMapsGeocoder http://codex.wordpress.org/Plugin_API/Action_Reference/save_post http://codex.wordpress.org/Function_Reference/wp_update_post http://codex.wordpress.org/Template_Tags/get_posts