Off-the-shelf SaaS vs custom: the real 3-year cost
29 Apr 2025, 03:47 pm · 3 min read
"It's only $45 a month" is how most software bills start. Then it's per user. Then the tier you need is $90. Then there's an AI add-on on top. Then you're paying for three tools that half-talk to each other. Over three years, the sticker price and the real price diverge fast.
The chart is indicative, but the shape is real: subscriptions scale with headcount and never stop; a custom tool is a larger up-front spend that then flattens. Somewhere between year one and year two, the lines cross.
When SaaS is the right call
Off-the-shelf wins when the problem is generic and someone's already solved it well, email, accounting, payroll. Don't rebuild those. You'll lose.
When custom wins
- The tool is your business process (how you quote, dispatch, inspect, bill).
- You're paying per-seat for features you don't use.
- You're gluing 3–4 apps together with spreadsheets and copy-paste.
- Your data is trapped and you can't get a clean export.
The line items nobody quotes you
The subscription is the headline. The real bill hides in the margins.
The integration tax
Two tools that don't talk mean a person copying data between them, or a third tool to join them. That person, or that tool, is a cost.
The onboarding drag
Every new starter learns three logins instead of one. Multiply that by turnover and it adds up quietly.
The export ransom
Leaving is where you discover your data is hostage: locked formats, throttled exports, or a fee to get your own records out.
The feature you rent for one field
You jump a pricing tier for a single checkbox everyone else on the plan is also over-paying for.
The 2026 line item: you now pay for AI twice
The newest twist is the AI surcharge. The tools you already rent have bolted their AI features onto a higher tier or a per-seat "AI add-on", so the plan you're on quietly costs more to keep doing the same job. You end up paying several vendors a premium for the same handful of AI tricks. A custom tool uses AI as one ingredient you control, on your own data, without a second subscription stacked on the first.
A simple test before you build
Not everything deserves a custom build. Before you commit, ask three questions:
- Is this how we're different? If the process is your edge, own it. If it's generic, rent it.
- Are we fighting the tool weekly? Workarounds and "the app won't let us" are a tax you're already paying.
- Can we get our data out clean, today? If not, you don't own your business, your vendor does.
Custom costs more to start and less to keep. A subscription is exactly backwards.
Own the software that is your business, rent the software that everyone runs the same way, and never pay a per-seat tax on the difference.