I have a field in the Opportunity section called Amount that was getting an Install charge from the standard products in the opportunity section. The problem is that now I've added a function to add a new product that is not in a price book, so for example if a we put 2 Standard products with install value of 100 and 1 non standard product with the value of 200 the custom field called Total_Value__c charge will be 400 but the Amount field will only show the values from a standard product (200).
The Amount field is the one that pops up on forecasts so I need it to show the total value of both non-standard and standard products.
Does anyone know how to update that field automatically and possible change all the historic field to be updated ?