Andrew Crossley

    How much money do I need to build an MVP?

    SHORT ANSWER

    A focused software MVP costs roughly £5,000–£15,000 built with AI-assisted tooling and a small scope, £20,000–£50,000 with a freelance or agency team, and £60,000–£120,000 for a complex or regulated product. The main cost driver is scope, not day rate: every extra flow adds design, build, testing and support cost. Budget 20% for post-launch iteration — that is where the learning is.

    Answered by Andrew Crossley, Fractional Chief Product Officer · Updated 2026-08-01

    Why it matters

    Founders budget for the build and forget the iteration. A launched MVP with no money left to respond to what it teaches you is a wasted experiment.

    Quoted ranges vary tenfold because scope varies tenfold. Comparing quotes without comparing scope is meaningless.

    How it works in practice

    1. 1

      Cost the flow, not the product

      Price each user flow separately. Founders are shocked how much of the budget sits in admin, billing and settings screens nobody asked for.

    2. 2

      Separate build from run

      Hosting, model inference, email, monitoring and support cost money monthly. Budget twelve months of run cost up front.

    3. 3

      Reserve the iteration budget

      Hold back 20-30%. Spending 100% on v1 leaves nothing for the version the data asks for.

    4. 4

      Choose the delivery model deliberately

      AI-assisted solo build is cheapest and fastest for simple products; an agency buys capacity but rarely product judgement; a fractional product lead plus a small build team is the middle path.

    Common mistakes

    • Spending the whole raise on v1 because it feels like progress.
    • Paying for a custom design system before proving anyone wants the product.
    • Underestimating AI inference costs at scale — model spend can exceed hosting within months.
    • Choosing the cheapest quote, which is usually the one that misunderstood the scope.

    FROM EXPERIENCE

    Three real budget shapes

    £8,000: one flow, AI-assisted build, managed infrastructure, live in five weeks, aimed purely at proving demand with paying pilot users.

    £35,000: two flows plus payments and light admin, small contract team with product leadership, eight to ten weeks, aimed at a seed raise with usage evidence.

    £90,000: multi-role product with integrations and compliance requirements — at this level, validate hard before committing, because the cost of being wrong is a full runway cycle.

    Frequently asked

    Can I build an MVP for under £5,000?

    Yes, if the scope is genuinely one flow and you use no-code or AI-assisted tooling. Complexity, not ambition, is what breaks that budget.

    How much should I keep for marketing?

    For a validation MVP, very little — you should be reaching users directly. Paid acquisition is a post-PMF cost.

    Is an agency worth it?

    For capacity, sometimes. For product decisions, no. Agencies build what you specify; the specification is the risky part.

    IN SHORT

    • £5k–£15k lean, £20k–£50k team-built, £60k–£120k complex or regulated.
    • Scope drives cost far more than day rates do.
    • Reserve 20-30% for post-launch iteration and budget twelve months of run cost.

    Idea to MVP in six weeks

    A validated, instrumented first product in front of real users.

    Idea to MVP in six weeks

    THE FRAMEWORK

    The Crossley Method: idea to first revenue in seven stages

    See the full method
    1. STAGE 1DiscoverWeek 1
    2. STAGE 2ValidateWeek 2
    3. STAGE 3PrototypeWeek 3
    4. STAGE 4Build MVPWeeks 3-4
    5. STAGE 5LaunchWeek 5
    6. STAGE 6First RevenueWeek 6
    7. STAGE 7ScaleOngoing