Create a Controlboxx product with product type 'DirectUpload'.
Go to the 'Staffs and options' tab.
In the 'Option Libary', create an option in the back office of the Webshop; for example, 'Number' with the option 'Pages' option below.
Right-click on the "Pages" option and choose 'Variable input'.
Under 'Type Calculation', select 'Surcharge' and click Save'.
Now add the parameters and set the panel as follows:

Add parameter
To add a new parameter, click Add parameter. The fields below the line are emptied if data was here.
Label
Label fills in as clear a name as possible. The orderer will see this name at the fill field in the shop.
Unit fee (€)
Please enter the price per page here.
Label
Label fills a name as clear as possible in the orderer will see this name in the fill field.
Minimum decrease
Enter the number of pages for the minimum number of pages that may be ordered.
Maximum decrease
Enter the number of pages for the maximum number of pages that can be ordered.
External Prefix
This is a label for Controlboxx and is used for counting the pages. Please include "PageCount" as an external prefix.
Query string mapping
This is used for counting black and white and color pages. Please fill in 'PageCountBlack' and/or 'PageCountColor'.
Then click on 'Save'. The variable input has now been added to the option with a minimum and maximum quantity. When the option is added to a product, it is checked for the specified variable value.
It is also possible to create different page options with different parameters so that a minimum and maximum value can be set per product.