Requesting help for adding values in power query.

I want to add values in a column together that are next to each other in the same column but It is for one invoice number that is in a different column. Any idea what formula I could use in power query?

Sorry about that. I went ahead and updated it and I am attaching an example file.

In column A you will see what are supposed to be example Invoice Numbers. There are 1 to 2 lines for each number depending on what items they purchased in column G. You can also see the pricing for each item in column H and the totals for the amounts purchased in columns I.

I need to get the totals for each each invoice, which basically is adding the totals of the items together, and put the grand invoice total in a separate column.

I am trying to do this in power query so when I get a report each month I can just drop it into a folder(like I have been reading online) and have it do this automatically for the thousands of lines I get each month.

Any help would be much appreciated!

I went ahead and added more to my example. I just read I was supposed to have some manually complete calculations.

Thank you for your reply. I do not think this is what I need. I am currently working with a pq and I am looking for a formula that would take the current information and add the to line totals together for a grand total and put it in a new column next to that data. Also, it has to display the grand total of the invoice on every line that has that invoice number. The invoice numbers are next to each other in column A. If you look at my second example I am adding together the green shaded numbers in column I, which would be the invoice total, then putting the invoice total under the total column but displaying the total on each line of that invoice. Same with the blue shaded numbers. If you look at the red shaded numbers, that invoice has only 1 line item so it would only display the invoice total once since it only has 1 line for that invoice.

I know I am asking for a lot and I appreciate the help. I have never used pq but from what I have read once I change 1 report how I want it I can drop all future reports into that folder and hit refresh and it would run the new report through those changes I made. I can see how it saves the changes in the box on the right side of the screen in excel as I am completing them. If I am mistaken about this tool please let me know.

Thank you!