Why London Dev Agencies Quote Six Months for a B2B MVP

You decide your wholesale business can no longer survive on a diet of emailed spreadsheets and manual data entry. A quote that touches five spreadsheets before it goes out is a liability, so you decide to commission an internal operations portal. You approach three providers for custom software development in London.

The quotes come back, and they all share the same structural flaw: they do not quote you for a finished piece of software. Instead, they quote you for a twelve-week "discovery phase", followed by an open-ended commitment to fund a six-person development team at £850 a day, per head, for the foreseeable future.

This is the traditional agency model. It is designed to sell you capacity rather than outcomes, and for B2B operators in the UK and Australia looking to fix broken workflows, it is an incredibly expensive way to buy technology.

Here is how the traditional custom software model broke, how AI-accelerated delivery has changed the commercials, and what you should actually demand when commissioning a B2B build.

The Capacity Trap of the Traditional Dev Agency

Historically, the barrier to building custom software was the sheer amount of manual typing required to get a computer to do anything useful. Because building took thousands of hours, agencies built a commercial model around selling those hours.

If you walk into a typical London agency today, you are met with an army of non-technical overhead. You pay for an Account Manager, a Scrum Master, a Business Analyst, and a Delivery Lead—none of whom write code. Their job is to manage the "agile process", running endless sprint planning sessions and retro meetings while you foot the bill.

This creates an inherent conflict of interest. Your goal is to get a working order-management portal shipped quickly so you can stop misplacing inventory. The agency’s goal is to keep their staff billed to your account for as many sprints as possible. Outsourcing custom software should not mean endless sprints; it should mean solving a business problem and moving on.

To de-risk their time-and-materials contracts, these agencies enforce massive "discovery" phases. They will charge £30,000 to produce wireframes, user personas, and a backlog of user stories before a single line of working code is written. By the time you realise the project is running over budget, you are already months into the engagement and held hostage by sunk costs.

AI-Accelerated Delivery Changes the Commercials

In the last two years, the mechanics of writing software have fundamentally changed. AI coding assistants and accelerated delivery frameworks mean that the actual generation of syntax—the boilerplate code that used to take weeks—can now be executed in days.

The bottleneck in custom software development is no longer typing code. The bottleneck is defining the business logic.

A machine can write a database schema instantly, but it does not know what your warehouse staff in Manchester are supposed to do when a pallet arrives with a damaged barcode. It does not know how your Australian distribution partner expects their commercial invoices formatted. That operator logic is the true value of the build.

When a studio uses AI-accelerated delivery, they shift the bulk of the effort from manual coding to architectural logic and edge-case management. This strips out the need for bloated six-person sprint teams. A lean team of two senior engineers, armed with modern AI tooling, can outpace a traditional agency team of ten. This dramatically lowers the cost of the build and shortens the time to market, shifting the UK MVP cost drivers in favour of the buyer.

Stop Treating B2B Ops Like Consumer Apps

A major reason London agencies bloat MVP scopes is because they treat internal B2B tools like venture-backed consumer apps.

If you are building a social network for teenagers, you need a bespoke, highly animated user interface. If you are building a freight tracking portal to replace a WhatsApp group and a Google Sheet, your users do not care about custom animations. They care that the data is accurate, the page loads fast, and the system does not crash when they upload a 10,000-row CSV file.

The B2B ops MVP requires a completely different approach. You must aggressively cut the fat:

• Standardise the UI: Do not pay a designer to invent a new date-picker or a custom dropdown menu. Use established, pre-built component libraries. They are accessible, heavily tested, and cost nothing to implement.
• Cut the admin dashboards: Everyone wants a beautiful dashboard with pie charts on day one. In reality, your operations manager just needs a daily automated email export of exceptions (e.g. "These five orders are blocked"). Build the charts later.
• Focus on the core transaction: If the software is meant to process wholesale orders, focus entirely on the order ingestion, validation, and passing that data cleanly to your ERP or accounting software. Everything else is a distraction.

When you force an agency to strip away the consumer-grade polish and focus entirely on utility, you quickly expose whether they know how to solve operational problems or if they are just good at making things look pretty on a screen.

Fixed-Price Outcomes vs Time and Materials

The most important decision you will make when commissioning custom software development in London—or anywhere else—is the commercial contract you sign.

Time-and-materials contracts (where you pay a daily rate for as long as the project takes) remove all financial pressure from the agency. If a feature turns out to be more complex than expected, you pay for the extra time. If a developer gets stuck, you pay for their learning curve.

Instead, you should demand fixed-price milestones tied to working software.

A modern, AI-accelerated product studio can map your core business logic in a focused scoping phase (days, not months). They can then commit to a fixed price to deliver that specific scope. This shifts the execution risk back onto the developer. If they use AI tools effectively to build the portal in four weeks, everybody wins. If they get bogged down, it eats into their margin, not your operational budget.

How to Select a Delivery Partner

When interviewing a studio or agency for your B2B build, skip the standard questions about their tech stack. Most modern stacks (React, Node, Python, Postgres) are perfectly capable of running your business.

Instead, test how they think about your money and their time:

1. Ask for a fixed price on a tight scope. Give them a single, highly constrained workflow—for example, "a portal where our 50 B2B clients can log in, view live inventory from our ERP, and place an order". If they refuse to estimate without a paid twelve-week discovery, walk away.
2. Ask how AI changes their billing. If an agency tells you they use AI coding assistants but their timelines and day rates look exactly like they did in 2019, they are pocketing the efficiency gains.
3. Check their default response to complex features. Propose a bad idea, like adding a real-time chat feature between warehouse staff and clients. A good B2B product studio will push back, tell you it is a waste of money, and suggest an automated status update instead. A bad agency will happily quote you 20 extra days to build it.

Moving from Discovery to Delivery

You do not need months of wireframes to validate that manually rekeying data is hurting your business. You already know the process is broken.

The goal is not to buy hours of development time; the goal is to buy a system that cuts the queue, stops the errors, and gets your team out of the inbox. Find a technical partner who treats your operational bottlenecks as problems to solve quickly with modern tools, rather than an excuse to bill for another sprint.

Useful tool

Try Samvara's Document Readiness Checklist — Export/import docs by mode.