Time-and-materials contracts transfer all delivery risk to you. Fixed-price reverses that.
With time-and-materials billing, if the project takes longer than estimated, you pay more. With fixed-price billing, if the project takes longer than expected, the developer absorbs the cost. The right model for defined-scope projects is fixed-price — every time.
You've received two proposals: one time-and-materials with a range estimate, one fixed-price. You want to understand what you're actually buying in each scenario.
The time-and-materials model is framed as lower risk for the buyer ("you only pay for the work done") but actually transfers all delivery risk to the buyer. An estimate of $40k on a T&M contract is not a commitment — it's a forecast. If the project takes $70k of developer time to complete, you pay $70k. The developer's incentive on a T&M contract is to bill hours, not to deliver efficiently.
Fixed-price contracts exist because buyers correctly recognise that a commitment to a price is more useful than a forecast of a price. When you buy a fixed-price deliverable, you know the cost before starting. If the project takes more time than expected to complete, that's a production problem for the developer, not a billing event for you.
The objection to fixed-price contracts is that scope changes invalidate the price. This is correct: if you add features after the scope is agreed, the price changes. But this isn't a disadvantage of fixed-price — it's the mechanism by which fixed-price maintains accountability. The scope is defined, the price is fixed against that scope, and any change to the scope is a renegotiation. This forces scope discipline that T&M contracts don't impose.
A clear framework for evaluating development contract structures — and the specific situations where each model is appropriate.
Cost certainty
Fixed-price: you know the total cost before starting. T&M: you know the hourly rate; the total cost is determined by how long the project takes.
Delivery risk
Fixed-price: if the project takes longer than expected, the developer absorbs the overrun. T&M: if the project takes longer than expected, you pay for the additional time.
Scope discipline
Fixed-price: scope must be defined before the price is set; changes require renegotiation. T&M: scope can be fluid; the meter runs regardless.
Developer incentive
Fixed-price: the developer is incentivised to deliver efficiently because they absorb the overrun. T&M: the developer is incentivised to bill hours because every hour worked is revenue.
Appropriate use case
Fixed-price is appropriate for defined-scope projects. T&M is appropriate for ongoing, exploratory, or continuous-scope work (like a retainer).
One honest number to start.
Fixed-scope, fixed-price. The number below is the starting point — final scope is built from your brief.
A clear framework for evaluating development contract structures — and the specific situations where each model is appropriate.
Three steps, every time.
The same repeatable engagement on every project. No surprises, no mystery, no billable ambiguity.
Brief & discovery.
We send you questions, then get on a call. Output: a written scope with every step, feature, and integration listed.
Build & ship.
Fixed schedule, weekly reviews. No scope creep unless you change the scope — and if you do, we reprice it transparently.
Warranty & retainer.
30-day warranty on every launch. Most clients stay on a monthly retainer for ongoing features and maintenance.
Why Fixed-Price Matters Here
The model is simple: you define the scope, we define the price, and the project is complete when the scope is delivered. The price doesn't change because the project took longer than expected. That's the commitment.
Related engagements.
Questions, answered.
Fixed-price is appropriate for projects with a definable scope — a new application, a specific set of features, an integration, a rebuild. It's not appropriate for ongoing work where the scope is continuously evolving (a long-term engineering retainer where requirements change weekly). For continuous-scope work, a time-and-materials or retainer structure is the correct model.
Scope changes after the project starts are handled as a change order — a written specification of the change, its impact on the delivery timeline, and the adjusted price. The original scope and price remain valid; the change order adds to both. Scope change orders prevent the scope creep that's the most common cause of project budget overruns.
If the scope was correctly defined and doesn't change, a fixed-price project doesn't run over. If the project takes longer than estimated to complete the agreed scope, the additional time is not billed to the client — it's absorbed as a delivery cost. This is the core accountability mechanism of the fixed-price model.
Fixed-price contracts require detailed scope definition and explicit change order processes. The protection for the developer is in the specificity of the scope — if the scope is ambiguous, the developer assumes the worst case when pricing. Well-defined scope benefits both parties.
A fixed-price core with a defined change order process for extensions is the most common structure for complex projects. Phase 1 is fixed-price for the core deliverable. Post-launch extensions are quoted as fixed-price change orders. The change order pricing is determined by scope definition, not time tracking.
Tell Ryel about your project.
Describe what you’re building and what outcome you need. You’ll have a written, fixed-price scope within the week.