Hard to tell. Personally, I have a column for the Brokerage amount. So Price of share multiple by number bought of sold = ?
Then Adjusted price with the brokerage added in for a purchase, but deleted out for the sale. But brokerage better to be identified in a separate coloumn. Sorry, that's all I can think of.
However, if poster is not adept at formulas in the spreadsheet, best to go for a beginner's course in spreadsheets. Pull the handle, from the correct formula all the way down the column and everything calculates.
