Short answer
Choose a fixed-price project when the scope is stable and the budget has to be fixed. Choose a retainer when you need a small, predictable amount of support. Choose a subscription when you have a live product, a changing backlog and want continuous, senior output without counting hours.
Fixed-price projects
Good for: a defined system with a stable spec and a budget that has to be agreed up front, such as a grant-funded build or a procurement process.
Where it breaks down: real products change as you learn. Every change becomes a change request with its own quote, and both sides spend time negotiating instead of building. When the project ends, the team moves on.
Hourly retainers
Good for: light-touch support on a stable system, where a few hours a month is enough.
Where it breaks down: AI tools have made many changes much quicker. Work that once filled a day might take an hour. Retainers measured in hours start to undersell what you get, and the provider ends up scrabbling to find enough work to fill the block. It’s a model built for a slower era.
Subscriptions
Good for: live products with a steady stream of features, fixes and improvements, and teams that want senior judgment built in.
Where it breaks down: if you have no product yet, or nobody who can prioritise and review, a subscription has nothing to work on and no one to sign it off.
Side by side
| Fixed price | Retainer | Subscription | |
|---|---|---|---|
| You pay for | A defined scope | A block of hours | Continuous output and judgment |
| Changes | Change orders | Come out of the hours | Go into the queue |
| Budget certainty | High, until scope changes | High | High |
| Who benefits from AI speed | Depends on the quote | Neither, really | You get more shipped |
| After launch | New contract | Same hours | Same queue |
How AI tools changed the maths
When building was slow, pricing by time roughly matched value. Now the build itself is fast, and the value sits in the layer on top: deciding what’s worth building, designing it so people understand it, and making it survive real users. Hourly pricing can’t capture that, and fixed prices for small products look odd next to something knocked up overnight in an AI app builder. That’s why we moved to a subscription. The longer version is here.
Can you mix them?
Yes. A common path is a Discovery Sprint to shape a new product, a fixed-scope build to launch it, then the subscription to keep improving it.
Questions
Do you still offer retainers?
Existing support arrangements carry on as they are. For new clients, the subscription has replaced hourly retainers because it’s simpler and gives better value.
Is a 12-month subscription term risky?
It’s a commitment, which is why it’s worth checking the provider first. We use a 12-month term because product work compounds: the better we know your codebase and business, the more each month is worth.