First clarify how an amount arises
The invoice should not be the first place the team considers the billing model. At project start, clarify whether amounts follow recorded time, agreed scope or a recurring period. Extra services and changes need their own decision process.
This guide describes possible workflows, not which models are available in which OOKI version. Evaluate the configuration and results with a suitable test project before choosing a product.
Three models, three different service bases
| Model | Basis in this example | Key points to clarify |
|---|---|---|
| Time-based billing | Reviewed activities × agreed rate | Billability, rounding and period |
| Fixed fee | Agreed scope and trigger | What is included and what counts as a change? |
| Recurring agreement | Defined period and service package | Start, end and handling of extra services |
Example: why total internal time is not an invoice amount
“Nordlicht Relaunch” has 110 recorded minutes. Of these, 90 are billable in this example. At €120 per hour, the net service basis is €180. The remaining 20 minutes stay in the internal effort view.
A second project uses a fixed fee. Time analysis supports internal costing but does not automatically set the invoice amount. Using the same hours export for both projects could override the agreed model.
Before drafting, the project lead checks the model assignment. Finance then reviews the draft's recipient, service description, amount and other required details. These tasks complement each other; they are not interchangeable.
Four handovers to the invoice
Record the service basis
Define the period, selected services and reviewed version. Keep previously transferred services identifiable so a repeat run does not accidentally duplicate them.
Generate a draft
Apply the agreed calculation to the reviewed basis. A draft remains a draft even if its layout looks finished.
Review independently
Check recipient, description, quantities, prices and other details in the generated document. A valid source file does not replace this check.
Separate sending and status
Record whether a document is reviewed, sent or paid. Downloading a PDF proves neither sending nor payment.
Corrections must not hide the origin
Editing an invoice draft item should not silently change the original time entry. They serve different purposes: time entries document work, drafts prepare billing. Their relationship must remain clear.
After sending, different requirements apply than for an unpublished draft. Clarify the correct correction procedure for the case. This workflow does not imply sent invoices may simply be overwritten.
Frequently asked questions
Should every task become an invoice item?
Not necessarily. A clear summary may be useful if the link to documented services and the agreement is preserved.
What does “ready for billing” mean?
Define it within the team. A useful definition combines an agreed model, complete service basis and clear responsibilities. A coloured status alone does not establish this.
From the guide to the sample project.
Try the steps in the OOKI demo: tasks, client view, time entries and invoice draft with fictional data. No login required.
Try the demo (DE)