Receiving Various Run Time Errors On A Simple Piece of Code

HG,
Part of the issue was that you didn't declare variables, like sRow, fRow etc. Also, use Option Explicit at the beginning of your code then "step" through your code and it will usually highlight the problem line(s) of code for you. It wont tell you specifically what's wrong with it, but at least you will know where the error is. to step through code, click any line in your code then press F8, this will go line by line through you code. Here is updated code for you...it may still error out on the ActiveSheet.Range...... line, but I'm not sure why yet..

Option Explicit
Sub test()

Dim rFind As Object
Dim fRow As Long
Dim sRow As Long

    With Range("b4:b10000")
        Set rFind = .Find(What:="", LookAt:=xlWhole, MatchCase:=False, SearchFormat:=False)
        If Not rFind Is Nothing Then
            fRow = rFind.Row
        End If
    End With
    
        With Range("b1:b10000")
        Set rFind = .Find(What:="ID", LookAt:=xlWhole, MatchCase:=False, SearchFormat:=False)
        If Not rFind Is Nothing Then
            sRow = rFind.Row
            sRow = sRow + 1
        End If
    End With

'Range(Cells(4, 2), (Cells(fRow, 4 )))

ActiveSheet.Range(Cells(sRow, 2), (Cells(fRow, 4))).AdvancedFilter Action:=xlFilterCopy, CopyToRange:=ActiveSheet.Range(Cells(4, 4)), Unique:=True

    Range("E4:F2000").Select
    ActiveSheet.Range("$E$4:$F$28").RemoveDuplicates Columns:=Array(1, 2), Header _
        :=xlNo
        
        
        

        

        

End Sub

LOL, they are to me as well....although some of them I understand a little better than I used to.

Luckily, I haven't seen that one to often....I don't think.
I think I have narrowed it down to the Action part of the code. When I break it down and step through it, it highlights that word.

Here is your runtime error BUT it won't solve your overall problem--you still have some issues. Remove the code in red.

ActiveSheet.Range(Cells(sRow, 2), (Cells(fRow, 4))).AdvancedFilter Action:=xlFilterCopy, CopyToRange:=ActiveSheet.Range(Cells(4, 4)), Unique:=True

The destination for your advanced filter copy overlaps with the source data. You are copying from column B:D and pasting to D. Also you are including the cost column in your copy, so nearly every row is unique anyway. Although I was able to do this manually in Excel with no error, it gave weird results and I have to wonder why you want to do that. Based on your formulas, I think it is an error.

Let's take a step back and talk about what it is you want to do. You want a unique list to use SUMIF to calculate costs. Please look at the attached and see if that gets you there.

To be clear, you see the result but I updated your macro and formulas so you should be able to wipe out columns F:G and run the macro again.