All calculators: to switch from positive to negative numbers or vice-versa, highlight the numbers to change in one column and right click, select change sign.  To put the same # or formula in multiple cells, enter the # or formula in the top cell, highlight the cells you want filled starting w/ that top one, select ALT  + DOWN ARROW    or right click and select “fill down”.

 

Anywhere there are cells underlined in blue inside the spreadsheets you can enter numbers or formulas in place of what is there, like to vary an interest rate.  Many boxes that say “other” can have a title typed in for insurance or extra fees so you know what the number relates to in that box.