I would rather that there is an audit trail as she is the type to receive a check and say she never got it and shred it.
OR, you write and mail a check, on time, every time for
years and
years. Towards the end of the CS obligation she says you haven't been paying. Whether she does it malice or simple incompetence doesn't matter.
Now unless you can prove every penny
paid you will have to pay it again, not to mention the hassle of having to prove it.
Basically, it's good strategy for any evil spirited child support receiver to challenge that they have not been
paid fully at some point before the CS obligation ends. If the numbers don't tally for whatever reason (actual nonpayment, accounting error, lost records, fire, war , disease, pestilence) and it comes up short then it must be
paid again. If it comes up over.........well, that's a gift and doesn't need to be
paid back.