To determine the lowest bank balance among the provided amounts, we have:
- $123.49
- $75.23
- -$123.69
- $75.89
- -$123.43
The negative balances indicate debts, so we need to compare both the positive and negative amounts.
The lowest balance is the one with the smallest value, which in this case is -$123.69.
Thus, the lowest balance is -$123.69.