How to hide rows in SSRS report?
Unless I'm missing some nuance, you will simply set the Row Visibility based on the value.

Right click on the detail line and select Row Visiblity...



In the window that pops up, select Show or hide based on an expression



Within that expression, you'll use logic like

=Fields!Total_Allocation.Value = 0 And Fields!Total_Actual_Cost.Value = 0