There is no limit in MapifyPro!
For a high number of locations, please ensure that you turn on clustering in the map settings. This means that when the map is zoomed out, a city with 10 map locations will show up with a single map pin with the number 10 inside it.
This is helpful for two reasons:
1. The map pins don't overlap when the site visitor zooms out.
2. Better panning and zooming for site visitors with slower computers/phones.