Custom fields
Add your own fields to any record, then filter, report and search on them like any built-in field.
Settings → Custom fields.
Add fields to customers, vendors, items, projects, employees, or any document type.
Types: text, number, money, date, yes/no, a dropdown of your own values, or a link to another record.
They are real fields, not notes. A custom field can be filtered on in a list, grouped in the custom report builder builder, required before a record can be saved, and shown on a printed document.
Industry editions add their own — turning on the construction pack adds retainage percent and cost code to the right records. Those behave identically to fields you create; the difference is only who defined them.
Removing a field hides it rather than destroying the data behind it, so switching an industry edition off and on again does not lose what you entered.