You can use the Input Form Manager to create custom input forms for creating, editing, and viewing documents. You can continue to use Classic Edition
The view of the application that you see when you first install the base managed package. or Extended Edition The view of the application that you see when you install one of the extension packages (such as the Cash Entry Extension package). For invoices, credit notes, and journals Extended Edition is integrated into the main package, but must be configured. if you prefer, but custom input forms display header, detail, and summary information on one page and better support "tab out" for moving from one field to another.
Default custom input forms are provided for the six document types: Sales Invoice, Sales Credit Note, Payable Invoice, Payable Credit Note, Journal, and Cash Entry. When you have enabled custom input forms in your org, you can start using the default forms or customize them to suit your business needs by creating your own forms. You can create separate Input and View forms, or a single Input & View form.
When building or modifying custom input forms you can:
- Specify which fields you require in the header, field, and summary sections.
- Quickly change the position of fields and columns.
- Remove unwanted fields.
If your org contains multiple companies, you can build different custom input forms for different companies. For example, you might want to build one custom input form for entering sales invoices in an SUT company, and a different custom input form for entering sales invoices in a VAT company. When you have built a form you must assign it to the companies that will use it, and activate the form.
Related Lists
Custom related lists and standard Salesforce related lists are supported on custom input forms for viewing documents.
Action Buttons
You can remove optional action buttons (such as the standard buttons Sharing and Submit for Approval) from a document type's standard page layout so that they are not displayed on custom input forms for that document type. If you inadvertently remove an action button that is required, it will still be displayed on custom input forms for that document type.
Custom Buttons
Custom buttons are displayed along with other action buttons on custom input forms for viewing documents provided that they have been configured as follows on the custom object for the document type:
- A custom button's Display Type must be Detail Page Button.
- A custom button's Content Source can be URL, Custom S-Control or Visualforce Page.
- A custom button must be included on the custom object's page layout assigned to users. If you are using the "Salesforce Mobile and Lightning Experience Actions" section on the page layout, you must add the custom button to that section from the Mobile & Lightning Actions category in the palette.
Printed Text
Users can maintain printed text when creating and editing sales invoices and sales credit notes. They do this by clicking the 
icon on the custom input form then clicking Printed Text to open a popup where they can select predefined text definitions and enter free format text.
Limitations
Before enabling custom input forms in your org, be aware of the following limitations:
- Custom Lookup Filters (Value or Field) are not supported. You may select a value that does not meet the filter criteria but an error message will be displayed when you try to save the document. However, when creating a custom input form you can filter Account lookup fields by account type
- Custom formula fields are not populated until you save the document.
- Custom input forms do not support payment schedules for sales invoices. Use Classic Edition or Extended Edition for sales invoices if you need to set up payment schedules.
- Custom input forms do not support income schedules for sales invoices. Use Classic Edition or Extended Edition for sales invoices if you need to set up income schedules.
- Custom input forms do not support currency override values.
- If you have enabled the flexible decimal places feature, custom input forms do not round decimal values for payable invoices, sales invoices, payable credit notes and sales credit notes, until you click Save or Save and Post.