Apologies yes, I was trying to see if there is a possible amount that fixes the rounding error.
I have put the prices back as:
Price for the item is 77.3912
Price for engraving is 26.0869
Tax rate is 15%
If I change decimal value to 1, then prices display as R89.0 which looks wrong.
The shopping cart total then rounds up way too much, so R119.00 is shown as R119.2 where before is was R119.02