; https://hledger.org/invoicing.html

2020-02-01 * (201602ab) AB Inc. | invoice
    revenues:consulting:ab     $-1000
    assets:receivable:ab        $1000

2020-02-15 * AB Inc. | payment for 201602ab
    assets:receivable:ab       $-1000  ; = $0  ; assert this if fully paid (optional)
    assets:checking             $1000