Hi ​@Abdessamad,

Tasks are for managing timelines and resource assignments, while Estimates are for budgeting and cost forecasting. And yes, estimates are tied to the Activity Planned Cost Source.

Hello ​@Abdessamad,

You can draw the distinction between “Tasks” and “Estimates” as follows and understand in how these two can be used in ‘budgeting and forecasting’ as well. 

Tasks: You can essentially use “Tasks” as an extension for further work that needs to be performed and distinguishable under a Project Activity. This can be done by splitting said additional work and creating different but unique task/s as their placeholders.

Moreover, Tasks come with “Task Start Date”, “Progress” and “Completed Date” that allows users to track the work completion which comes in handy for administrative purposes (if such granularity is required). In a way this allows users to create and organize work check lists under Project Activities.  

Most importantly though based on how your client has been using tasks, they’ve probably used Tasks to enter “Planned Cost/Revenue” and “Planned Hours” against a “Cost Element”, where these figures get lumped in to “Planned Cost/Revenue” and “Planned Hours” columns in the Project Monitoring > Cost, Revenue and Hours tabs respectively.

When carrying out budgeting and forecasting you have the option to create a budget/forecast from “Project Planned Costs/Revenues” (when copying values from a Project) thus ultimately carrying the values entered under Tasks in to the Budget/forecast. In this approach you can compare the “Planned Costs” versus the “Actual Costs” (Used/Planned Committed and Committed Costs) within the Periodic Reviews. 

Estimates: Under Activity Scope and Schedule > Estimates tab (or via “Activity Estimates” page), users are allowed to manually enter “Estimated Costs/Revenue/Hours” against respective Cost/Revenue elements. These values gets lumped on to the respective Cost Revenue Elements and gets displayed under the “Estimated Cost/Revenue/Hours” columns in the “Project Monitoring” page >  Cost, Revenue and Hours tabs respectively. 

**It is important to note that “Estimated Cost” can be used as the “Planned Cost Driver” for the Activities as well. If this is the case figures that users manually enter under “Estimated Cost” will get translated in to “Planned Cost” in Project Monitoring > Cost tab and the values in these two columns will always be the same. 

When it comes to Budgeting and Forecasting depending on the “Planned Cost Driver” configuration,
a) Planned Cost Driver = Estimated Cost - Then users can copy over either planned/estimated to the budget and forecast and compare the actuals against the copied value

b) Planned Cost Driver is NOT estimated cost rather assuming it’s ‘connected objects’ you have an additional layer of estimated costs/revenues and hours which could be the first set of high level project estimations based on early predictions.  - In this case users can copy over the “Estimated Costs/Revenues/Hours” so that they have the option to compare “Estimated” versus “Planned” versus “Actual” values in their periodic reviews. 

Hope this helps! :)

Cheers!
Sachitha D