Custom vs Off-the-Shelf Software: How to Decide

“Should we buy software or have it built?” is really four smaller questions. Answer them in order and the decision usually makes itself — here it is without the agency sales pitch, from someone who tells about a third of inquiries not to hire him.

Q1: Is this problem common or is it yours?

Accounting, email, payroll, calendars, CRM-in-general: common problems, buy them. QuickBooks and its peers have thousands of engineer-years in them; no custom build competes. But the workflow that makes your business yours — the weird quoting logic, the way jobs flow from call to crew to invoice, the report your industry needs that no vendor ships — that’s where off-the-shelf starts costing you in workarounds.

Q2: What do the workarounds cost?

The honest price of off-the-shelf isn’t the subscription; it’s the spreadsheet glue. Every “we export it, fix it in Excel, then paste it into the other system” is a recurring tax — do the same math as in the automation guide (minutes × frequency × hourly value). When the annual workaround tax exceeds a build’s one-time cost, the “cheap” option quietly became the expensive one. Also count per-seat fees at your real headcount, three years out.

Q3: Do you need 100% custom, or 10%?

This is the modern answer most comparisons miss: the best builds are hybrids. Keep the commodity tools, and custom-build only the connective tissue — a script that syncs system A to system B, a small dashboard over the data you already have, a portal that wraps your weird workflow around a standard backend. Serverless makes these small: a form-and-function here, a scheduled job there (see what a serverless function is). You get custom fit without custom everything prices.

Q4: Can you own what gets built?

If you do commission custom work, the contract question that matters most: you own the code and it’s documented. A custom tool you can’t take to another developer is vendor lock-in with extra steps. (Everything I build hands over the repo and a plain-English doc of how it’s wired.)

The decision in one paragraph

Buy off-the-shelf for common problems. When workarounds pile up, don’t leap to a six-figure platform rebuild — scope the smallest custom piece that removes the biggest tax, usually an integration, an automation, or a small internal tool, often a few hundred to a few thousand dollars. That’s the exact tier of custom software I build: scoped and quoted before any work, sized to pay for itself.