We have four different types of custom columns that can be added into ServiceBox with different functionality.
The 'Dropdown' and 'Multi-Select' build up their settings through usage on the unit, customer, jobsite or work orders they are attached to. So if you enter 'High' on one unit's column, that entry then is displayed as an option on the other unit's entries. This allows you to build up a set of valid entries over time with the flexibility to add new entries as you go.
We have two other types 'Restricted Dropdown' and 'Restricted Multi-Select' which allow you to set the exact entries that are allowed to be used. After selecting this type, you will be able to enter a comma delimited list of valid values for these columns. The user will only be able to select from this list without adding any new items.