Google Map with Point Editing

Looking to have a simple google map built that will allow anyone who visits the link to add their own points to the map and it will save these point automatically after each point is added. This could be saved to a flat file or database. There will be multiple users working on the map at once. The purpose of the map is to crowd source the mapping of certain features found on the base map. - The basemap will be google satellite view - The map will use the full browser screen and start with a fixed extent at a our area of interest. - When a user clicks to create a new marker, don't want to have any popups appear to enter attributes (They will be creating 1000's of points by clicking features on the satellite photo, so needs to be quick and easy to create the next point). - When the user clicks on an existing marker, have a popup with a delete button to remove the point. - Markers symbols will need to be a very small red circle, not the default google maps marker. - Will need to have a KML overlay embedded. This is a simple polygon layer that will outline the areas of interest that point will be added to. I will provide this KML file. - Need a way to get the saved marker coordinates out of the system as a kml or csv. If all the data is written to a flat file this would work to just download the file but looking for some advice on this since there will be multiple users working on the map at the same time. Looking for quick turn around time and for someone to start right away. Our time zone is GMT -7 Thanks,