Written technical specification
Agreed before development, so scope changes are visible rather than silent.
Phase 1 · Build
SaaS & Custom Platform Development
When the software is the product. Web applications with user accounts, permissions, dashboards and billing — built properly, scoped honestly, and owned entirely by you.
- Start from £4,950
- Build in stages
- Full code ownership
Users1,284
Plans3
MRR↑ 18%
Roles
Admin
Member
Viewer
POST /api/signup201 createdBilling ✓
Full code ownership
The problem
Most custom software costs more than it should
Custom development goes wrong in a predictable way. The scope is agreed loosely because nobody wants to slow the project down.
Building starts. Requirements surface that nobody thought about — permissions, edge cases, what happens when two users do the same thing at once. Timelines slip. The budget doubles. Everyone ends up unhappy with something that mostly works.
The other failure is quieter and more expensive: the thing gets built and shouldn’t have been. A configured combination of existing tools would have done the same job for a tenth of the cost, and nobody said so because saying so meant a smaller invoice.
We’d rather tell you that at the scoping stage. It costs us a project and saves you £30,000.
2×the budget, once the requirements nobody thought about surface
1/10the cost of the configured tools that would have done the same job
£30,000what saying so at the scoping stage can save you
Do you actually need custom software?
How to tell
Work through these honestly before commissioning anyone.
- 01
Could a configured platform do it?
Airtable, Notion, GoHighLevel, Zapier and similar tools now cover an enormous amount of what used to require custom development. If your requirement is “a database, some forms, a few automations and a dashboard”, you probably don’t need software written. You need tools configured properly, which is a much smaller job.
- 02
Is the software the product, or a tool for the business?
If you’re selling access to it, custom is likely right. If it’s an internal tool that saves your team time, configured platforms usually win on cost and on how fast you can change your mind.
- 03
How unusual is your logic really?
Every business feels its process is unique. Most aren’t, at the level software cares about. The genuinely unusual parts are worth building; the rest can often be handled by something existing.
- 04
Can you fund version two?
Custom software isn’t a purchase, it’s a commitment. Version one is roughly half the total cost over three years. If the budget only covers the build, it will decay.
- 05
Who maintains it?
Custom code needs updating, hosting, monitoring and occasional fixing. Budget for that or plan to inherit a problem.
Our position
Many of the businesses that ask us for custom development leave the scoping call with a cheaper recommendation. That’s a good outcome, and it’s why the scoping call is worth having even if you go elsewhere afterwards.
Our process
How a platform build runs
- Step 01 of 06
Discovery & scoping
We map what the software must do, what it must not do, and what could be handled by existing tools.
- Step 02 of 06
Technical specification
A written spec covering features, data model, integrations and constraints — agreed and priced before development starts.
- Step 03 of 06
Design & prototype
Interface design and an interactive prototype you can click through, so problems surface before they cost money.
- Step 04 of 06
Build in stages
Developed in phases with working software at each stage, rather than disappearing for four months.
- Step 05 of 06
Testing & launch
Functional testing, security review, load testing where relevant, then deployment and handover of everything.
- Step 06 of 06
Support & iteration
Ongoing development, monitoring and maintenance, because version one is never the finished thing.
What’s included
In every custom build
Security review
Authentication, permissions, data handling and dependency checks before launch.
Interactive prototype
Click-through design you can test before a line of code exists.
Staged delivery
Working software at each phase, not one delivery at the end.
Documentation
Written properly, so another developer could take over if needed.
Full code ownership
Repository, hosting and every credential transferred to you on completion.
Who this is for
Custom development probably fits if
- 01You’re building a product you intend to sell access to
- 02Your workflow genuinely doesn’t fit existing platforms
- 03You need user accounts, permissions and role-based access
- 04Existing tools have become the bottleneck rather than the solution
- 05You can fund ongoing development, not only the initial build
- Sounds like you?Book a scoping call
Probably not a fit if
A configured platform would do
The budget only covers version one
The requirement isn’t clear enough to specify yet
We’ll say which of these applies at the scoping call — and CRM & Automation is often the cheaper answer.
CRM & AutomationWhere this fits
Build is phase one of four
Phase01of 04Build
Custom platforms sit in phase one, but they interact with the rest differently.
A SaaS product usually needs a separate marketing site for phase two, since application interfaces aren’t indexable content. And phase three matters more, not less — a product with signups needs onboarding sequences, trial follow-up and churn handling, which is CRM work.
If you’re building a SaaS product, phases two and three are how you get users, not optional extras.
Pricing
SaaS development pricing
SaaS & Custom Platforms
Swipe to compare
| Tier | Price | Timeline | What it covers |
|---|---|---|---|
| Working CoreMost Popular | £4,950 | 3–4 weeks | One user type, the single feature that matters most, real data, genuinely usable |
| Starter Platform | £11,950 | 5–7 weeks | Internal tool, single user type, forms, database, reporting dashboard |
| SaaS MVP | £19,950 | 8–12 weeks | Multi-user, authentication, roles and permissions, billing, admin panel |
| Full Platform | £34,950 | 14–20 weeks | Complex logic, third-party integrations, multiple user types, built to scale |
| Enterprise | From£55,000 | Scoped | Bespoke architecture, compliance requirements, high scale |
Ongoing: Maintenance £395/month · Development Retainer £2,250/month (4 days) · day rate £595. Design only: Web App Interface Design at £2,950, if you’re building elsewhere.
It starts with a paid discovery
£1,450Credited in full against the build if you proceed within sixty days.
A written technical specification, data model, interactive prototype and a fixed build price.
We charge for this because a proper specification takes days rather than minutes, and because free scoping is how custom projects end up vague. Vague is how they double in price halfway through.
If you decide not to build, or to build with someone else, the specification is yours. It’s a genuinely useful document to take to any developer.
Why we recommend starting at Working Core
Most custom software goes wrong because the entire thing was priced before anyone understood the scope. Building the core first means you see working software within a month, then decide whether to continue — with real information rather than a specification document and a hope.
You can stop at any stage. Everything built is yours regardless.
For context: a comparable MVP typically runs around £55,000 from a UK team of this kind, and £85,000 from a full London agency. The difference is that you’re not funding an office — not that we cut the timeline or the team.
01How much does custom software cost?
From £4,950 for a working core, £11,950 for a starter platform and £19,950 for a multi-user MVP with billing. Discovery produces a fixed price first.
02Why is the discovery paid when your other audits are free?
Because a proper specification takes days of work, not an automated scan. It's £1,450, credited in full against the build, and the document is yours either way.
03Can I start small and add to it later?
Yes, and we'd recommend it. Working Core gives you usable software in three to four weeks. Each stage after that is approved separately, so you're never committed further than you want.
04What if the scope changes mid-project?
It usually does. Changes are quoted and agreed in writing before being built, so the budget moves visibly rather than arriving as a surprise invoice.
05Can you take over an existing project?
Sometimes. We'd audit the codebase first and tell you honestly whether continuing or rebuilding costs less. Inheriting undocumented code isn't always the cheaper path.
06Who owns the code?
You do, completely. Repository, hosting, domains and credentials transfer to you on completion. The documentation exists so another developer could take over.
Next step
Find out what you actually need built
Book a scoping call. We’ll map the requirement, tell you which parts genuinely need custom development and which don’t, and give you a realistic cost — including when the honest answer is that you shouldn’t build it.
- Based in Ilford, East London
- Call +44 7366 355562
- Mon–Fri, 10am–6pm