This was one of the things I actually wrapped into the LTUGtools utilities that I built in the Paradox database program, and posted to the LTUG usergroup page on Yahoo!Groups back in...  I want to say about 2008 or so.  You would set to year & module to look for, make sure you have an Option path specified, give the Invoice# to change, and the % increase to apply.

  Paradox would open the saved invoice file and replace all of the fee amounts with the higher.

VERY few people ever bothered to get a free download of Paradox Runtime to actually make use of the utilities, though.  Ahhh, well.

What you CAN do is:

 - go to your Option path for the (new) year, after everything rolls up;

 - scroll down and find your selected Invoice file;

 - right-click and "Open With" NotePad;

 - (i would recommend search/replace common features of the pricing lines with 'Tab', so that you get distinct columns in a spreadsheet);

 - copy/paste into a spreadsheet, now with one entire column of nothing but pricing numbers;

 - do your column of math to get the new amounts, and then copy/ paste AS VALUES (not formulae) the new amounts over the old;

 - remember to delete (or just not-copy) the column of new prices that uou just did math on;

 - copy/paste the now-updated info back to the open text file you started with;

 - search/replace 'Tabs (now that you are done with columns) with whatever it was to start with, like = or $;

 Ź close file and Save;

 - open that invoice in that module in that year of Lacerte, and double-check for accuracy.

I am speaking in generalities because we never used Lacerte invoices, so I do not recall the filename; nor do I recall the structure of the lines inside, after looking at it that time & solving the issue I never had cause to visit it again.

Robert Kirk
LTUGtools