How an unlimited development retainer actually works
Unlimited" is a word that deserves suspicion. Here is exactly what it means here, including the limits.
Most development is sold by the project. You agree a scope, agree a price, and anything outside it becomes a change request. That model is simple to sell and quietly terrible for both sides.
We work on a monthly retainer with unlimited development inside a fair use policy. Because "unlimited" is a word that should make you suspicious, here is precisely what it means.
What you get
You ask for things as they occur to you. No change request, no re-quote, no three-day wait for a number. You say the invoice screen needs a filter by site, and it gets added.
We work in priority order, which you set. Each month we agree what matters most. If something urgent lands mid-month, it goes to the top and something else slides. That is your call, not ours.
Everything is supported. Bugs are not billable. If we built it and it breaks, we fix it. That is not generosity, it is the incentive working properly — we would rather build it right than be paid twice.
The system keeps moving. This is the real point. A business changes constantly, and software built once and abandoned starts working against you within about eighteen months.
Where the fair use line sits
This is the part most firms are vague about, so here it is plainly.
One active workstream at a time. We build one significant thing at a time and build it properly. If you need three parallel workstreams, that is more than one retainer's worth, and we will say so rather than quietly doing all three badly.
A reasonable queue. Asking for things faster than any team could build them does not make them appear faster. It just means a long list. We will tell you when the queue has stopped being realistic.
In scope: your systems. The retainer covers the software we look after for you. It does not cover building an entirely separate product for a different business, or becoming your IT department.
Emergencies are emergencies. Production down, nobody can work — we drop everything. "I would like this by Friday" is a priority, not an emergency, and treating everything as urgent means nothing is.
Honestly, we have rarely had to invoke any of this. It exists so the arrangement stays sane when a business has an unusual month.
What it costs
Between £1,200 and £4,000 a month, depending on how much development you actually need and how complicated the estate is.
At the lower end: a stable system, steady improvements, a few days a month. At the upper end: active development, multiple integrations, a system your operation genuinely runs on.
No minimum term, thirty days' notice. If it stops being worth it, stop. A long tie-in is how firms keep clients who would otherwise leave, and we would rather earn the month.
Why not just pay per change?
Because of what it does to your behaviour, not ours.
When every change costs money, you stop asking for small ones. The £200 tweak that would save an hour a week never gets requested, because raising it feels like a negotiation. Multiply that by two years and you have a system everyone works around rather than with.
We have inherited a lot of those systems. They were built competently and then frozen, and the business quietly built a shadow process in spreadsheets around the parts that no longer fit.
On a retainer, the cost of asking is zero. So people ask, and the software keeps up.
Who it does not suit
One-off projects. If you need a thing built and then genuinely nothing else, pay for the thing. We will quote it fixed and part as friends.
Businesses that do not change. If your operation works exactly as it did three years ago and you expect the same again, you do not need continuous development.
Anyone who wants to buy hours. We do not sell time, we sell progress. If you want a timesheet of what was done on which afternoon, we are the wrong fit — that is a contractor arrangement and there are good people who do it.
How it starts
Usually a fixed-price first build so you can see how we work, then the retainer picks up from there. Some clients go straight onto a retainer with an existing system we inherit.
Either way the first month is the one where we learn how you actually work, which is the part that makes everything afterwards quicker.
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