Don't know if anyone is interested in a very simple way of displaying locations on Google Maps, but the attached is how I do it in one app. Might not be of interest to old hands, but might encourage some newer users.
It's not as complicated as trying to display multiple locations as described in the Code Lib.
There are two buttons [Show] and [Hide] as not everyone wants to see the maps all the time. The maps change as you select different Clients.
Feedback welcome.