Time, Expense, and Billing Operations
Capturing execution data
Execution data is the raw material of the whole system. Understand time entry structure: date, project, task, role or category, hours, billable flag, and chargeability. Know approval workflows (submit, approve, reject, recall) and period controls such as timesheet periods, cutoffs, and locks. Understand expense management: expense categories, policy limits, receipts, per diem, corporate card reconciliation, and the difference between reimbursable and non-reimbursable items.
Turning data into invoices
Billing consumes approved, unbilled transactions. Know the billing methods - time and materials, fixed fee, milestone, progress - and how each selects transactions. Understand unbilled transaction status (available, on hold, already invoiced), invoice corrections and credit notes, and write-offs. Understand that a transaction can be billed only once and that reversing an invoice returns transactions to the unbilled pool.
Traps
Classic distractors: assuming unapproved time can be billed (it cannot); assuming an expense is billable just because it was approved (billability is a separate attribute); confusing a credit note with a payment; and assuming changing a rate on a contract retroactively reprices already-invoiced transactions. Also watch for period-lock questions: once a period is closed, entries require adjustment, not direct edit.
Worked example
A consultant logs 8 hours at a bill rate of 200 and a cost rate of 110, plus a 50 taxi marked billable at cost. The invoice line is 1,600 + 50 = 1,650; margin is (200−110)×8 + 0 = 720 on the labor, with the expense passed through at zero margin.