What You'll Learn
- The 5 key factors that determine buy vs build
- How to calculate true total cost of ownership
- When hybrid approaches make sense
- Real examples from 50+ client decisions
The Real Question Isn't Buy vs Build
The question "should we buy or build?" is actually the wrong framing. The real question is: What creates the most value for our specific situation?
We've seen companies waste millions building software that already exists, and we've seen companies cripple themselves trying to force off-the-shelf solutions into unique workflows.
The answer depends on five factors:
When to Buy Off-the-Shelf Software
Buy when the problem is common and the solution is mature. Here are the clear signals:
The Problem is Solved
Accounting, CRM, email marketing, project management—these are solved problems. Thousands of companies have the same needs, and excellent solutions exist.
Speed is Critical
You need it working in days or weeks, not months. Off-the-shelf means immediate deployment.
It's Not Your Core Business
You're a logistics company—you don't need custom accounting software. Focus your custom development on logistics, not back-office functions.
80% Fit is Acceptable
If a tool does 80% of what you need and you can adapt your workflow for the other 20%, buy it.
Examples: Buy
- → CRM: HubSpot, Salesforce, Pipedrive
- → Accounting: QuickBooks, Xero, FreshBooks
- → Email Marketing: Mailchimp, ConvertKit, Klaviyo
- → Project Management: Asana, Monday, ClickUp
When to Build Custom Software
Build when your needs are unique and the software is a competitive advantage. Here are the signals:
It's Your Core Product
If your business IS software (SaaS, platforms, apps), you obviously build. But also if software enables your unique value proposition.
No Solution Exists
You've searched extensively and nothing does what you need. Industry-specific workflows often fall into this category.
Off-the-Shelf Costs More Long-Term
When SaaS pricing scales with users/usage and you'll be paying $10,000+/month indefinitely, custom might be cheaper.
Integration Complexity
You need deep integration with legacy systems that off-the-shelf tools can't handle.
Examples: Build
- → Custom workflows: Industry-specific processes no SaaS handles
- → Internal tools: Admin dashboards, operational systems
- → Customer-facing apps: Your product/portal
- → Data pipelines: Complex ETL with proprietary logic
The Decision Matrix
Score each factor 1-5, then multiply by weight. Higher score = lean toward build.
| Factor | Weight | Score 1 (Buy) | Score 5 (Build) |
|---|---|---|---|
| Uniqueness | 3x | Common need | Completely unique |
| Strategic Value | 3x | Back-office function | Core to business |
| Time to Deploy | 2x | Need it yesterday | Can wait 6+ months |
| 5-Year TCO | 2x | SaaS is cheaper | Custom is cheaper |
| Internal Capability | 1x | No dev resources | Strong dev team |
Score Interpretation
- 11-25: Strongly favor buying off-the-shelf
- 26-40: Consider hybrid approach or customization
- 41-55: Strongly favor building custom
True Cost Comparison
Don't just compare sticker prices. Calculate the full 3-5 year total cost of ownership (TCO).
Buy: Hidden Costs
- Monthly subscription × 60 months
- Per-user fees at scale + growth
- Implementation/onboarding one-time
- Training & change management ongoing
- Integration costs (Zapier, etc.) monthly
- Workarounds for missing features time cost
Build: Hidden Costs
- Initial development one-time
- Ongoing maintenance (15-20%/yr) × 5 years
- Hosting & infrastructure monthly
- Security updates & compliance ongoing
- Feature requests & enhancements as needed
- Documentation & knowledge transfer initial + updates
Rule of Thumb
If SaaS costs exceed $3,000/month ($36K/year), seriously evaluate custom. At $5,000+/month, custom often wins on pure economics.
The Hybrid Approach
Often the best answer is neither pure buy nor pure build, but a combination:
Buy + Integrate
Use off-the-shelf for most functions, build custom integrations to connect them exactly how you need.
Buy + Extend
Choose platforms with good APIs, then build custom features on top. Example: Shopify + custom fulfillment logic.
Build Core + Buy Periphery
Build your unique value proposition custom, use SaaS for everything else. Example: Custom product + Stripe for payments + SendGrid for email.
Common Mistakes
Building What Already Exists
"We need custom CRM because ours is special." No, it's not. Your sales process is 95% identical to everyone else's. Use Salesforce.
Underestimating Maintenance
Custom software isn't "done" when it launches. Budget 15-20% of initial cost annually for maintenance, updates, and improvements.
Ignoring Opportunity Cost
6 months building internal tools is 6 months not building your product. What's that worth to your business?
Forcing Bad Fits
Spending more on workarounds and integrations than custom would cost. If you're fighting the tool daily, it's the wrong tool.