Hello,
- Other than security the biggest issue on altering past financial data is making additional errors while correcting errors. If somebody changes cash to credit card on "ticket b" instead of "ticket a" that creates additional problems. For example if you don't store printed tickets elsewhere you won't be able to find the error. I don't know why but when we permit corrections that matching need happens everyday...
- If you permit error corrections you should give your admin pin so they'll be able to correct their errors when you leave for a reason. Believe me when you do that the most shared information between staff becomes the admin pin
Like I stated on the post John referenced we can make payment corrections or refunds through Cash. For making it easier we can implement a correction workflow similar to John's suggestion but we'll never permit altering past financial data.
Now I remembered a little trick. There is a "Only for Old Tickets" setting on print jobs. When you duplicate a bill print job, include it in mapping and mark it as "Only for Old Tickets"... SambaPOS will use that print job when printing paid tickets. It might be useful for adding big "REPRINTED FOR YOUR INFO, DO NOT PAY" title on old ticket reprints.