Custom software or off-the-shelf? A practical way to decide

"Should we build this or buy something off the shelf?" It's one of the most expensive decisions a business makes, and it's often made on gut feel. Here's a more reliable way to think about it.

Start by assuming you'll buy

For most needs — accounting, email, basic CRM, file storage, payroll — someone has already built a product that does it better and cheaper than you could, because they've spent years and thousands of customers refining it. The default should be to buy, and you need a real reason to override it.

Build when the process IS the business

The reason to build is when the thing you're automating is how you're different from competitors. If your edge is a particular way you schedule jobs, price quotes, or route work, an off-the-shelf tool forces you to work like everyone else. That's when custom software pays for itself — it encodes the thing only you do.

The questions that actually decide it

• Does a tool exist that covers 80% of this? If yes, can you live with adapting to its way of working? Often the honest answer is yes.
• Is this workflow a competitive advantage, or just admin? Build the advantage. Buy the admin.
• What happens when the person who set it up leaves? Off-the-shelf tools have support and docs. Custom software has to be built so someone else can maintain it — or it becomes a liability.
• What's the real cost at scale? Per-seat pricing that's cheap at 5 users can be brutal at 50. Sometimes building wins on long-run cost — but do that maths honestly.

The expensive mistake, both ways

Building what you should have bought wastes months on a worse version of something you could have licensed. Buying what you should have built forces your business to fit the software instead of the other way round.

What we tell clients

When someone asks us to build something, our first job is to check whether they should. If a small monthly tool solves the problem, that's the advice — even though it means less work for us. The build conversation only starts once buying is genuinely off the table.