Breaking out Tax for each unique value

Before
Before Breakout.PNG

After
After Breakout.PNG

I am thinking this is possible in VBA, the reason I think its possible is that I am able to write out the logic for it. However, I don't currently have the knowledge to make this work and this is the #1 problem we have with our invoicing. Here is my logic

1. For each cell in Transaction Description look for "TAX"
2. If found, assign activecell.currentregion to myRange
3. Look for unique values in LINE PO column, and assign each unique value to a variable
4. Insert a row at each change in unique value of LINE PO column
5. Drag the last unique value down to fill recently inserted row
6. Rename Transaction Desc in new row to TAX
7. Divide TAX Value by (sum of account - TAX) to get TAX % || in this situation, it would be (9.16 / 111.30) = ~8.23%
8. Multiple each variable SUM of Trans Amount by the percentage collected
9. Insert the value on the new TAX line that was inserted

Anyone have any ideas on where to start?

*Edit: Included sample workbook

As this has been sitting a few days, I am offering a formula based proposal.
This proposal adds two helper columns, which may be moved and/or hidden for aesthetic purposes to the 'Before' data range.
The first helper column (Z) is populated using: =IF(W3="tax","",IF(OR(V4<>V3,W4="tax"),SUM(COUNTIFS(V$3:V3,V3),1,MAX(Z$2:Z2)),""))
The second helper column (AA) is populated using: =IF(ISNUMBER(Z3),SUMIFS(Y$3:Y3,V$3:V3,V3)*(SUMIFS(Y$3:Y$7,W$3:W$7,"TAX")/SUMIFS(Y$3:Y$7,W$3:W$7,"<>TAX")))
In the output data, the account, location and unique columns are populated using: =IF(MAX($Z$3:$Z$7)< ROWS($A$1:$A1),"",INDEX(T$3:T$7,AGGREGATE(15,6,(ROW(T$3:T$7)-ROW(T$2))/($Z$3:$Z$7>=ROWS($A$1:$A1)),1)))
Column W is populated using: =IF(T17="","",IF(V18<>V17,"TAX",INDEX(W$3:W$7,AGGREGATE(15,6,(ROW(W$3:W$7)-ROW(W$2))/($T$3:$T$7=$T17)/($U$3:$U$7=$U17)/($V$3:$V$7=$V17),COUNTIFS($V$17:$V17,$V17)))))
Column X is populated using: =IF(W17<>"MONTHLY STANDARD SVC TRASH","",INDEX(X$3:X$7,AGGREGATE(15,6,(ROW(W$3:W$7)-ROW(W$2))/($T$3:$T$7=$T17)/($U$3:$U$7=$U17)/($V$3:$V$7=$V17)/(W$3:W$7=W17),1)))
Column Y is populated using:

Formula:

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Let us know if you have any questions.

The MAX() is used to add the number of rows that are already being assigned to the other unique's. If we had used SUM(COUNTIFS(V$3:V3,V3),1,Z2)) then in cell Z6 it would have displayed a value of 3 since cell Z5 is blank.
As to rows 17:24 which are populated using four formulas, I am going to ask that you utilize the Evaluate Formula feature and watch at least one sample of each formula. If you have a specific questions afterwards I will do my best to explain.
As to scaling, as long as the unique values change as shown in the sample file, then it should work. However it might be a good idea to upload another file, in a new post, that shows what happens to the unique values when the account and/or location changes.
Let us know if you have any questions.