COD or cash on delivery can be enabled for any service type that is desired and set an amount as maximum for it. This setting can be accessed through the admin center.
Admin Center → Services → Action / New record → Service setting tab → Other → Is COD active
By enabling this field, you grant customers the option to insert an amount when creating a new order, and the driver will be aware that they should collect some cash upon delivering that order. The maximum amount the customer can insert is also managed here.
Admin Center → Services → Action / New record → Service setting tab → Other → Max COD limit