On paper, an organisation sells either time (time and materials) or an outcome (fixed price). In practice, the same client signs a time-and-materials engagement with a day allowance not to be exceeded, a fixed-price lot paid on acceptance, and a service billed as progress is made. When the invoicing tool only knows one or two models, the rest ends up in a spreadsheet, recalculated by hand every month.
AlibeeZ comes at it from the other side: one engine carries all four models, and the contract says which one applies. The panel above sums them up, each with its calculation rule and an illustrative example, and makes the key point: one client can carry all four in parallel.
The four models, and what the engine calculates
Time and materials: approved days × day rate
The most common case. The days approved in timesheets are multiplied by the day rate set in the contract. For example, 18 days at €620 gives €11,160. Nothing is calculated by hand: the amount follows directly from approved time, and the invoice is generated from it.
Capped time and materials: capped at the envelope
The client pays for time spent, but within an envelope of days or budget set in the contract. The whole point is to see the cap coming. AlibeeZ tracks how much of the envelope is used and alerts you at the threshold you set: with a 40-day cap, an alert at 36 days leaves time to discuss an amendment with the client before the question comes up on an invoice.
Milestone billing: on the contractual milestone
The price is fixed, and it is billed in instalments tied to contract milestones. When a milestone is reached, the matching share becomes billable, for example 30% of the lot on V1 sign-off. A milestone reached is one of the sources of invoice generation, just like approved time.
Progress billing: the measured percentage
The amount billed follows the project’s measured percentage of completion, and the cumulative amount stays visible: in the panel’s example, 62% complete and €65,100 to date.
Beyond these four models, the engine models the contractual rules specific to your contracts, recurring billing for example, so that approved time translates into amounts that match the contract with no copying or reworking.
The model is set per contract, not per client
This is the structural choice. In AlibeeZ, the billing model is a property of the contract. So one client can carry a time-and-materials engagement, a fixed-price lot and a progress milestone, each with its own payment terms and VAT. When invoices are generated, each contract produces its lines by its own rule, and you do not have to split the client into several records to work around the tool.
The model can even be set as soon as the deal is won. With the HubSpot connector, a deal marked “won” creates the client, contract and project in AlibeeZ, with its billing model. The invoiced amount then flows back onto the HubSpot record: the salesperson sees what their deal actually produced.
What the contract holds besides the model
A billing model is not enough to make an invoice right. The AlibeeZ contract also holds the rules around it, so none of them has to be looked up at issuing time.
- Payment terms: due date (for example 45 days end of month), late penalties, early-payment discount where relevant.
- Schedules, which say when each share is to be invoiced and collected.
- Expense rebilling: with margin, at cost or at a flat rate, as negotiated. Expenses reach the invoice from expense claims, with no re-keying.
- Alert thresholds on the envelope, the purchase order ceiling or the budget.
These rules are settings, not development: you configure them in AlibeeZ, contract by contract.
VAT, entities and currencies: the cases that break spreadsheets
Mixed contracts are not the only thing that pushes people towards spreadsheets. Groups that invoice from several entities or in several countries know this well. AlibeeZ handles them in the same engine.
| Topic | What AlibeeZ does |
|---|---|
| VAT | A rate per country, per entity and per type of service |
| Legal entities | Numbering, sequences, VAT and currency specific to each entity |
| Currencies | Invoicing in another currency, tracked in the original or converted currency, at the rate of the invoice date, kept afterwards |
| Overseas subsidiaries | Invoices passed to Xero or MYOB in the local currency, without head office losing the consolidated view |
The historised rate matters more than it looks: a dollar invoice issued on 30 June keeps that day’s rate. Yesterday’s figures do not move when the exchange rate changes.
What it changes for your teams
No more side spreadsheet. Mixed cases, once the exception handled by hand, go through the same engine as plain time and materials. The contract says what is to be billed, and generation applies it.
Fixed price steered, not just billed. On a fixed-price project, billing follows milestones or progress, but profitability depends on the remaining effort. AlibeeZ tracks both on the same project, so a drift shows up before it eats the margin.
Demos on your real contracts. Because models are settings, a capped time-and-materials deal, a milestone fixed price or a multi-currency case can be tested on a real contract during the demo.
Going further
How these rules become draft invoices is covered in invoice generation in AlibeeZ. For steering fixed-price projects (remaining effort, loss at completion), read how AlibeeZ solves fixed-price forecasting. And for rebilling expenses with or without margin, see expense rebilling in AlibeeZ.
Frequently asked questions
How are mixed time-and-materials and fixed-price contracts handled?
Per contract rather than per client: one client can carry a time-and-materials engagement, a fixed-price lot and a progress milestone, each with its own payment terms and VAT.
What happens when capped time and materials approaches its ceiling?
AlibeeZ alerts you at the threshold you set on the envelope, before the cap is reached. You have time to warn the client or get an amendment signed.
Can we invoice in a currency other than the euro?
Yes. The invoice is tracked in the original or converted currency, with the rate of the invoice date kept afterwards, and each entity can have its own currency.
Are payment terms the same for every client?
No. Due date, late penalties and schedules are defined contract by contract, so one client can have different terms depending on the service.
