Hello
Please check attachment.
If you checked "Property Type' field, you for every possible value we have numeric ordering.
like
Apartment == 1
Commercial == 2
....
If you check folder from RealEstateManager with image for markers {your site}/components/com_realestatemanager/images
There every image for marker look like
marker-1.png
marker-2.png
marker-3.png
....
So :
marker-1.png for Apartment
marker-2.png for Commercial
........
Regards
OrdaSoft team