Adding unit names/numbers to the property would help organise your list of properties in a better way.
To add a unit to a property-
- Go to Properties, by clicking on the Properties icon on the left hand-side menu
- Click on the 'Details' tab of the property for which you would like to add a unit
- Click on Add unit in the top right corner, add unit details as given in the screenshot below
- Click Save
Please Note: This 'Add unit' option is shown only in case you chose the property type as multi-unit property while creating the property itself.