Fixed Price vs Time & Materials vs Monthly Retainer: How Design and Development Agencies Charge
Agencies charge by fixed price, time and materials, or monthly retainer. Here's how the three compare, when each one fits, and what to ask before you sign.
Design and development agencies charge in three main ways: fixed price (one agreed price for a defined scope), time and materials (you pay for the hours or days actually worked), and monthly retainer (a fixed monthly fee for a set amount of capacity or a dedicated person). Fixed price suits projects with a clear scope, time and materials suits work where the scope will change, and a retainer suits ongoing work or teams that need extra designers or developers every month.
The right model depends less on the agency and more on how well you can define what you need today.
How do the three pricing models compare?
| Fixed price | Time and materials | Monthly retainer | |
|---|---|---|---|
| You pay for | An agreed scope | Hours or days worked | Reserved monthly capacity |
| Budget certainty | High | Low to medium | High per month |
| Flexibility to change scope | Low — changes need a change request | High | High within the capacity |
| Best for | Websites, landing pages, defined MVPs, redesigns | Complex or exploratory products | Ongoing design and development, dedicated team members |
| Main risk | Scope disputes, padded quotes | Costs grow without control | Paying for unused capacity |
| What you must provide | A clear brief | Active involvement and prioritisation | A steady flow of work |
When should you choose a fixed price?
Choose a fixed price when you can describe what "done" looks like: a company website, a landing page, a store on Salla or Shopify, a brand identity, or an MVP with an agreed feature list. You get a known cost and a known delivery date.
The trade-off is that changes cost extra. A good fixed-price agency will define scope precisely, list what is excluded, and agree up front how change requests are priced. If a quote has no scope document behind it, the fixed price is not really fixed.
When should you choose time and materials?
Choose time and materials when the product will evolve as you learn — early-stage platforms, complex integrations, or work where research will change the plan. You only pay for what is done and can reprioritise weekly.
The trade-off is budget uncertainty. Protect yourself with a monthly cap, weekly reports of time spent, and a clear backlog you prioritise yourself.
When should you choose a monthly retainer?
Choose a retainer when the work never really ends: continuous product design, ongoing improvements after launch, or when you need dedicated designers or developers inside your own team. Software houses and product companies often use a retainer as an alternative to hiring — see our guide to staff augmentation for software houses.
The trade-off is that unused capacity is usually not refunded. Retainers work best when you have a steady pipeline of work and a named person on your side to direct it.
Can you combine models?
Yes, and it is common. A frequent pattern is a fixed-price discovery or design phase, followed by fixed-price or time-and-materials development, then a monthly retainer for improvements after launch. Each phase uses the model that matches how certain the scope is at that point.
What to ask any agency about pricing
- What exactly is included and excluded in this price?
- How are change requests priced and approved?
- How many rounds of revisions are included?
- Who owns the design files and source code on completion?
- What happens after launch — bug-fix period, support, maintenance?
- For retainers: what is the notice period, and does unused time roll over?
The cheapest quote is often the one with the vaguest scope. Compare what is included, not only the number at the bottom.
How Flowlix prices work
Flowlix, a product design and development studio in Ismailia, Egypt, uses a fixed price for defined projects — websites, landing pages, e-commerce stores, brand identities and MVPs — with a written scope and a quote sent within 48 hours of a consultation. For ongoing needs, Flowlix offers monthly retainers, including dedicated designers and developers who work inside a client's team. Clients are in Egypt, Saudi Arabia and the Gulf.
Flowlix starting prices:
- Landing page: from USD 800 (SAR 3,000 / AED 2,940 / QAR 2,910)
- Website: from USD 1,200 (SAR 4,500 / AED 4,410 / QAR 4,370)
- Mobile app design: from USD 1,200 (SAR 4,500 / AED 4,410 / QAR 4,370)
The final price depends on scope, and every project gets a fixed, written quote before work starts.
Frequently asked questions
Which pricing model is cheapest?
None is cheapest by default. Fixed price is cheapest when the scope is clear; time and materials is cheapest when the scope would otherwise be over-estimated; a retainer is cheapest when you have steady, ongoing work.
Do agencies charge hourly or per project?
Most studios quote per project for defined work and monthly for ongoing work. Pure hourly billing is more common with freelancers and for small, unpredictable tasks.
Is a deposit normal?
Yes. Fixed-price projects usually start with a deposit and are paid in milestones tied to deliverables. Retainers are usually paid monthly in advance.
Talk to us
Book a free consultation on WhatsApp and tell us what you're building — we'll recommend the pricing model that fits and send a clear scope and quote within 48 hours. One team for design and development, with AI in our workflow.