Dedicated ERP or off-the-shelf — how to choose

The answer is: off-the-shelf, in most cases. Worth stating up front, since a piece written by a company that builds dedicated systems might be expected to argue the opposite.

An off-the-shelf ERP wins when your process resembles other companies' in the industry and the budget is limited. Licence plus rollout is then cheaper than building, and the risk is lower. A dedicated system makes sense in a narrower set of situations — and this piece is about recognising when you're in that set.

Four deciding questions

1. Is your process a source of advantage?

If a company makes money because it does something differently from its competitors, flattening that "differently" into a standard module costs more than the licence. If, on the other hand, the process is standard and the advantage lies elsewhere — relationships, price, location — an off-the-shelf system is the right choice.

2. What does adapting the off-the-shelf system cost?

This question settles it most often. Ask the vendor for a quote on the modifications you need. If the sum of licence, rollout and modifications approaches the cost of building your own system, the choice stops being obvious — because for the same money you get either an 80%-fit system, or a 100%-fit one.

3. How many users do you have?

A per-user licence changes the maths over time. At twenty people the difference is negligible. At two hundred, over a five-year horizon, it can exceed the cost of building your own system.

4. How much will the process change?

A company in a stable industry, doing the same thing for a decade, fits well into an off-the-shelf system. A company changing its business model every two years will keep fighting limitations that can't be worked around except through the vendor.

The five-year comparison

Comparing only the rollout cost is misleading. Below is an example for a manufacturing company with 120 users. The figures are illustrative — meant to show the cost structure, not a quote.

The takeaway isn't "dedicated is cheaper." It's: at this scale the costs converge, so the decision should be made on a different basis than price. At thirty users the same table looks completely different, and the off-the-shelf system wins outright.

Signals that an off-the-shelf system has stopped fitting

• The team keeps the "real" data in a spreadsheet next to the system.
• A key report is produced by exporting to Excel and stitching it together by hand.
• Every process change requires a ticket to the vendor and waits for quarters.
• You're paying for modules nobody ever turned on.
• A new hire is learning less the system than the list of workarounds the team invented.

One of these signals is normal friction. Three or more mean the cost of the mismatch has exceeded the cost of change.

A third path that's rarely discussed

The choice isn't binary. A common and underrated approach is to keep an off-the-shelf ERP as the finance-and-accounting core and build your own modules where the company is genuinely atypical.

Accounting, HR and payroll are regulated areas where an in-house build is an expense with no return — the rules change every year and someone has to keep up. A production module, or handling a specific sales channel, is exactly where a custom fit pays off.

The condition is an ERP with a decent API. Without one, this path is closed — and that's an important criterion in choosing an off-the-shelf system that almost nobody asks about before signing.

What not to weigh in the decision

"Everyone in the industry has X." Your competitors made that decision at a different scale, in a different year, with a different process.

The sales demo. Every system looks good in a demo the vendor prepared. Ask for access to a test environment and run your own real case through it — ideally the most unusual one you have.

The promise that "it'll get configured." Ask who will configure it, how long it'll take, and what a consultant's day costs. The answers are sometimes surprising.

How to make this decision properly

Do two things before you choose.

First: write down your process as it actually is, workarounds included. Those workarounds are information about what the previous tool was missing — and the best material for testing candidates.

Second: ask both types of vendor to quote the same, written-down scope. As long as one is quoting a licence and the other a build, the offers aren't comparable.

Only once you have both of those does the "dedicated or off-the-shelf" conversation stop being a matter of opinion and become a calculation.