A source can be recorded in several areas.
You can add a source when creating or editing an appraisal via the Appraisal Source dropdown menu.
Or when editing a listing under the Listing Information section.
A source can also be added to a Buyer lead via the Source dropdown menu.
To customise the list of available Appraisal/Listing/Buyer Lead sources, go to Settings > CRM > Sources.
To add a new Source, click the '+ Add source' button.
Select an existing Source to edit the name, or delete it.
Note: A source cannot be deleted once it has been applied to an appraisal or listing.