I agree with my colleagues that all payments should be traceable and verifiable years from now. In addition to noting the name of the child, month of payment and that the payment is in fact child support in the memo section of the check, I would also keep a journal and/or spreadsheet detailing the amount and date of all payments.
In addition to documenting payments, if you know how much you and the Father make in income, the amount of the payments should be calculated utilizing the Florida Child Support Guidelines.
Finally, the best way to avoid future problems with child support arrearages is to establish a child support order and pay directly to the State of Florida Disbursement Unit. With an order, you'll know the exact amount of your child support obligation; and by paying through the Florida Disbursement Unit, it will not be necessary to document your payments in the future.
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Pay by check only and write "child support" in the memo line of the check. Make sure to keep copies of the checks and download copies of the cancelled checks if your bank allows you to do that.
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