What counts as off-the-shelf and what counts as custom?
An off-the-shelf app is a subscription product with a fixed set of features, such as bill capture, approval routing, payment reminders or expense claims, that connects to your accounting software through the vendor's integration. A custom workflow is built for your steps, usually on an automation platform or in code, and connects to each system through its API. Between the two sit configurable platforms such as Zapier, Make, n8n and Power Automate: the platform is off-the-shelf, but the workflow you build on it is custom, and someone has to own and maintain it.
When does an off-the-shelf app fit?
An app fits when its way of working matches yours closely enough that the gaps can be handled by small changes to your process. The vendor maintains the integration when the accounting software changes its API, which saves you that work, and other customers' feedback shapes the product. Test the app on your own documents before committing, because demonstrations use clean examples. Check the plan limits as well: a plan priced per document or per user can cost more than expected once your peak months are counted.
- Your process is close to how most businesses do the same task.
- The app covers every step, including your most common exceptions.
- Your volume sits within a plan you are comfortable paying for.
- You accept where the vendor stores and processes your data.
- You want the vendor to keep the integration working when systems change.
When does a custom workflow fit?
A custom workflow fits when the job crosses systems that no single app connects, or when the rules that matter most are particular to your business. It also fits when you want an AI step in the middle of a process, such as reading free-text emails and deciding where each one goes. The cost is that you own the maintenance: when a connected system changes its API, the workflow must be updated.
- The process touches several systems, such as email, a job system and Xero.
- Your exceptions follow rules that no app offers as a setting.
- You need to change the rules without waiting for a vendor's roadmap.
- You want control over where data is processed.
How do the running costs compare?
Apps usually charge per user, per transaction or by volume tier, so costs grow as the business grows. A custom workflow has a build cost, then hosting, platform fees, AI usage and support. Third-party charges apply to both. Xero, for example, moved app developers to five usage-based plans, with new terms for existing developers from 2 March 2026, and app vendors set their own prices. A custom integration using a Xero custom connection needs an additional monthly subscription that the organisation buys from Xero. Compare both options over the same period, using written quotes from each vendor. Our own pricing is on the pricing page or quoted after a short scoping conversation.
What do you own, and what happens if you leave?
With an app, you own your data but not the logic; leaving means exporting what the vendor allows and moving to another product. With a custom workflow, ownership depends on the agreement: ask who owns the workflow, the hosting account, the credentials and the documentation. Xero limits each organisation to five uncertified apps, while custom connection apps do not count toward that limit, so a business with many connected tools should check where it stands before adding more. Whichever you choose, write down how you would leave before you start.
How do you decide for a specific process?
Work through one process at a time. Map the steps and exceptions first. List the apps that claim to cover the process and test the best two on your own sample documents. Write down every gap and how you would handle it: change the process, add a manual step or build around it. If the gaps are small, use the app. If closing them needs a custom workflow anyway, compare the cost of building the whole process with the cost of the app plus the custom pieces around it.
Hypothetical example: invoice capture for a building supplier
Hypothetical example: a building supplier receives about 300 supplier invoices a month (an assumed figure). A capture app reads most of them and posts bills to Xero, which covers the common case. Two gaps remain: invoices must be matched to deliveries recorded in a separate yard system, and some suppliers send one PDF containing several invoices. The business keeps the app for capture and adds a small custom workflow that splits multi-invoice PDFs and checks each bill against the yard system before approval. Neither option alone covers the process. In this example the business compares quotes and judges the combination cheaper to run than rebuilding capture from scratch.