We are building a budget in Spreadsheet based on the template Construction Budget. One thing we are trying to do with Spreadsheet is eliminate all possible paths for human error that could have occurred in Excel.
For instance, in Excel, one could Sum a column range, and later add another row to the bottom of the column and completely forget that the summed range didn’t update to reflect the new row!
To help avoid this, and with the Construction Budget in mind, what would you advise for best practices. As I see it there are two possible solutions:

Indent all of the cost codes once more, and add a row at the top of the table that sums all descendant cells.

Add a row at the bottom that sums all parent sums above.
Can you advise what you think is the least likely to cause human error? Also, what would the correct formulas be to achieve either 1 or 2?
Thanks so much!