The useful question is not which option is more sophisticated. It is which option supports the work well enough, at a cost and level of responsibility the business can sustain. A familiar workflow may fit an existing product. An unusual requirement may justify a tailored solution.
Start with the important requirements
List the outcomes the system must support, the integrations it needs and the constraints that cannot move. Separate genuine requirements from preferences. Test the most difficult steps rather than judging only the demo's smoothest route.
For an existing product, ask whether you can complete a realistic end-to-end task without falling back to hidden spreadsheets. Check permissions, exports, approval rules, exception handling and access to your data. A feature name in a comparison table does not establish that it works in your context.
Compare the whole cost
Include licences, implementation, migration, configuration, integrations, training and support. For custom software, include hosting, monitoring, maintenance and the responsibility for updates. A one-off build price is not the lifetime cost.
A hypothetical business might compare a subscription tool with a custom internal portal. The subscription appears cheaper initially, but requires a separate integration and several manual workarounds. The portal has a higher initial cost and more maintenance responsibility. Neither option wins until those assumptions are tested.
Understand what you are taking ownership of
With an existing product, the provider controls its roadmap and service. With a custom build, someone must own the source, deployment, support and security work. Ask what happens if your supplier changes or the person who knows the system leaves.
Look at how you can export your records and move to another solution. Use a small sample export to test the answer. Include attachments, relationships and meaningful history where those matter to the workflow.
Consider a combination
An existing system may cover the core records while a small tailored interface handles a specific gap. That can avoid rebuilding common functions, but the integration still needs an owner and a plan for failure. Combining products is a design decision, not free glue.
Test the risky assumption first
Run a bounded trial or prototype around the requirement most likely to change the decision. Set a maximum effort for that exercise. Agree how the result will be assessed and when you will stop.
Use the automate-or-replace decision to establish the scope, then calculate realistic costs. Choose an option whose trade-offs you can explain and whose ongoing responsibility someone can actually own.
