There are additional options for your map markers. You can change the output by going to Listing Types Display Map Marker.
You can change your marker output to render any of your icons, custom icons, custom field value (like price or title) or image.
Set default marker location
You can set the listing default marker position by going to Listing Types (edit your listing type) Listing Fields, then find the Location field and set the default location need to pre-define.
The map center will be triggered, while your map is empty and there are no markers to display. You can manage this by going to Listing Types Settings Explore General Default map latitude / longitude.