At some point a B2B website needs a new capability. Maybe it is a quoting tool, a portal style dashboard, or tight integration with systems like Business Central. The question becomes, do we build a custom WordPress plugin or should we look for a hosted SaaS product that already does most of this.
This checklist walks through the considerations that usually decide the answer. You can use it in internal discussions or as a template when you compare options with your development or IT partners.
1. Clarify What You Are Actually Solving
Start with the problem, not with tools.
- Write a one sentence problem statement for this capability, for example reduce quote turnaround time or allow customers to see current rentals and invoices.
- List the three to five critical outcomes you want, for example fewer manual touches, fewer errors, self service status, better data for sales.
- Decide what must be in version one and what can wait, so you do not over build on day one.
- Note any hard constraints such as regulatory requirements, data residency, or internal approval gates.
2. Data And Integration Requirements
How deeply the solution touches your data often pushes you toward one option or the other.
- Does the capability need real time access to ERP or CRM data, or is daily sync sufficient.
- Will it create or update records in systems like Business Central, or is it mostly reading data.
- Do you need to enforce complex business rules that already live in your ERP or line of business systems.
- Are there existing APIs or integration layers you can reuse, or would the solution be the first consumer.
- Will the system need to be aware of internal concepts such as dimensions, custom fields, or bespoke workflows.
When integration is shallow and mostly one way, SaaS can be a better fit. When integration is deep and must respect internal rules and staging patterns, a custom plugin that talks to your own APIs often wins.
3. Ownership, Flexibility, And Roadmap
Think about how often this capability is likely to change.
- Is this a core differentiator for your business or more of a supporting utility.
- Do you expect to adjust logic frequently as you learn, or is the process relatively stable.
- Will other systems depend on this feature in the future, for example internal portals or partner tools.
- Do you want full control over the roadmap, or are you comfortable living within the options a vendor provides.
If the feature is central to how you sell or deliver, owning the implementation through a custom plugin can be worth the extra responsibility. If it is a non differentiating commodity capability, SaaS is often enough.
4. Total Cost Of Ownership
Compare the lifetime cost, not just the first invoice.
- Estimate build cost for a custom plugin including design, development, testing, and deployment.
- Estimate maintenance cost, for example plugin updates, security fixes, feature changes, and regression testing after WordPress or PHP upgrades.
- For SaaS, project subscription costs over three to five years including likely tier upgrades.
- Include integration work in both cases, since SaaS often still needs custom integration code or a connector plugin.
- Factor in internal time, such as admin configuration, user training, and support for both options.
A custom plugin is often front loaded. SaaS is usually spread over time. The better choice depends on your time horizon and whether you plan to reuse the plugin pattern across multiple sites or business units.
5. Risk, Reliability, And Vendor Lock In
Consider how each path fails when something goes wrong.
- For SaaS, what happens if the vendor is acquired, changes pricing, or retires features you rely on.
- Can you export your data in a usable format if you leave the SaaS platform.
- For a custom plugin, who owns the code and who is responsible for keeping it secure and compatible over time.
- Is there more than one developer or partner who could realistically support or extend the custom plugin.
- Do you have internal monitoring for errors and performance issues for whichever path you choose.
Owning code reduces vendor lock in but increases operational risk if you do not have a clear support plan. SaaS shifts operational risk to the vendor but introduces dependency on their business decisions.
6. Security, Compliance, And Data Sensitivity
Some capabilities touch data that has to be handled carefully.
- Will this feature process personal data, financial data, or operational details that competitors would value.
- Are there industry regulations or customer contracts that restrict where data can live or which third parties can access it.
- Does the SaaS vendor provide documentation about security practices, certifications, and audit trails.
- For a custom plugin, do you have secure hosting, patching, and access controls in place for WordPress and any back end APIs.
- Do you need fine grained control over logs and retention that SaaS may not provide.
When data is highly sensitive or heavily regulated, a custom solution running on infrastructure you control can be easier to align with compliance, as long as it is designed correctly.
7. User Experience And Brand Integration
Some SaaS products embed easily into your site, others always feel like a separate app.
- How important is a seamless, on brand experience inside your WordPress theme.
- Does the SaaS product allow styling and layout customization that match your design system.
- Will users need to jump to a separate domain or portal with a different navigation model.
- Can you control URLs and breadcrumbs for the feature, or are they dictated by the vendor.
- How well does the solution work on mobile and within your existing performance budget.
When the feature is central to your site experience, a custom plugin lets you design exactly what you need. For back office or internal tools, a separate SaaS interface may be fine.
8. When A Custom WordPress Plugin Is Usually The Better Fit
The custom route tends to make sense when several of these statements are true.
- The capability is tightly coupled to your unique processes or pricing models.
- Deep integration with systems like Business Central or internal APIs is required.
- You need precise control over data flows, staging tables, and logging.
- The feature is an important part of your competitive differentiation.
- You have or can retain a partner with the skills to build and maintain the plugin over time.
- You may want to reuse the plugin pattern across multiple sites or clients in the future.
9. When A SaaS Product Is Usually The Better Fit
SaaS is often the right answer when these conditions hold.
- The capability is common and non differentiating, for example generic live chat, simple ticketing, or basic scheduling.
- Internal teams do not want to own software maintenance or deployment pipelines for this feature.
- A mature SaaS exists that covers at least 80 percent of your requirements.
- The SaaS offers supported integrations or webhooks that cover your basic data needs.
- Predictable subscription cost is easier to budget for than a one time build plus variable maintenance.
10. Hybrid Options To Consider
In many cases the best answer is not purely custom or purely SaaS.
- Use SaaS for the heavy lifting, such as authentication or billing, and a custom plugin for the WordPress user experience.
- Build a thin custom plugin that wraps a SaaS API and handles integration with Business Central or other internal systems.
- Start with SaaS for validation and plan for a later custom build once requirements are stable.
- Use a custom plugin for public facing features and a SaaS portal for internal or partner only functionality.
11. Simple Scoring Framework
If you want a quick structured decision, you can score each option from one to five on the dimensions below and compare totals.
- Fit with requirements and integrations.
- Control over roadmap and flexibility.
- Security and compliance alignment.
- Total cost of ownership over three to five years.
- Risk profile you are comfortable with.
- User experience and brand fit.
This does not replace judgment, but it helps surface where custom and SaaS differ in ways that matter for your business.
How Elephas Helps With Custom vs SaaS Decisions
Elephas works in both worlds. We design and build custom WordPress plugins and integrations, and we also connect clients to SaaS platforms when that is the better fit.
- We help clarify requirements in the language of processes and data, not just features.
- We assess integration depth with Business Central, CRMs, and other systems so you understand the real complexity.
- We estimate build and maintenance effort for custom options and compare them with realistic SaaS costs.
- We design architectures that leave room for change, including hybrid approaches that combine SaaS and custom code cleanly.
The goal is not to always build or always buy. The goal is to choose the option that gives you the right balance of control, cost, and reliability for the specific capability you are adding to your WordPress stack.
