
Consider this scenario: a manufacturing company spends $38,000 on an "AI-powered quality control system" from a US vendor. Looked incredible in the demo. Slick interface, real-time dashboards, the works.
Six months later? It's catching maybe 40% of defects. Their old manual process caught 85%.
The vendor's response: "Your data isn't formatted correctly. You need to hire a data engineer."
Translation: They sold a generic model and hoped the problem was generic too.
This pattern happens constantly. And the reverse happens too - companies burning $150k building custom AI for problems that a $500/month SaaS tool would solve.
So here's a practical framework for making this decision. No theory. Just the questions that separate good investments from expensive lessons.
This sounds obvious. It's not.
Generic problems look like:
For these: Buy. Microsoft Copilot, Notion AI, Intercom, Claude—they're trained on millions of examples of these exact tasks. You won't beat them with custom development unless you have very unusual requirements.
Specific problems look like:
For these: Build. No off-the-shelf tool has your context. The context is the value.
Ask yourself: "If my competitor subscribed to the same tool tomorrow, would they have the same capability?"
Businesses often spend 3 months evaluating AI solutions for problems that cost them $8,000 a year.
Before anything else, do the maths:
| Factor | How to Calculate |
|---|---|
| Hours spent on task per week | Ask the team (they'll know) |
| Fully-loaded hourly cost | Salary ÷ 48 weeks ÷ 38 hours × 1.3 (super, leave, overheads) |
| Annual cost | Hours × Hourly cost × 48 weeks |
| Error/rework cost | Estimate based on historical issues |
Example: Accounts payable team manually processing 200 invoices/month.
If the solution costs $50,000 to build plus $500/month to run, you're looking at 18-month payback. That's solid.
If the solution costs $200,000? Walk away.
This is where most evaluations fail.
A chatbot giving a wrong product recommendation is embarrassing.
An AI approving a $50,000 invoice to the wrong supplier is catastrophic.
Risk matrix:
| If AI is wrong... | Impact | Recommendation |
|---|---|---|
| Customer gets slightly wrong info | Low | Automate fully, monitor weekly |
| Internal team wastes 30 mins | Medium | Automate with human spot-checks |
| Financial transaction is wrong | High | Human-in-the-loop required |
| Regulatory/legal breach possible | Critical | Human approval mandatory, AI assists only |
The Australian angle: Under the Privacy Act, you're still liable even if an AI system makes the error. "The algorithm did it" is not a defence. Build your approval workflows accordingly.
This is the killer.
Half of AI projects that fail don't fail because of bad models. They fail because the data is scattered across 14 Excel files, 3 legacy systems, and one guy's email inbox.
Before you build anything, audit:
| Data Requirement | Red Flag | Green Light |
|---|---|---|
| Historical records | "We'd have to export from the old system" | "It's all in our ERP with API access" |
| Consistent formatting | "Every sales rep has their own template" | "We've had standard templates for 3 years" |
| Volume | "We do about 50 of these a year" | "We process 500+ per month" |
| Labels/outcomes | "We don't really track if it worked" | "We have win/loss data on everything" |
Rule of thumb: If you can't pull 12 months of clean, labelled data in a week, you're not ready to build. Start there.
Here's what vendors don't mention: AI systems decay.
Off-the-shelf tools: The vendor handles maintenance. You pay monthly. Simple.
Custom builds: You own maintenance. Forever.
Budget reality check:
| Item | Buy (Annual) | Build (Annual) |
|---|---|---|
| License/hosting | $6,000-24,000 | $3,000-12,000 |
| Vendor support | Included | N/A |
| Internal maintenance | ~5 hours/month | ~20 hours/month |
| Model retraining | N/A | Quarterly minimum |
| Integration updates | Usually included | Your problem |
If you don't have someone technical who'll be around in 2 years, think carefully about custom builds.
After all that, here's the actual framework:
| Metric | Before | After |
|---|---|---|
| Generic problem + < $20k annual cost | Low priority | Don't bother (manual is fine) |
| Generic problem + > $20k annual cost | Evaluate options | Buy SaaS |
| Specific problem + < $50k annual cost | Consider customisation | Buy SaaS + customise if possible |
| Specific problem + > $50k annual cost + good data | High opportunity | Build custom |
| Specific problem + > $50k annual cost + bad data | Requires prep work | Fix data first, then build |
| Any problem + critical risk if wrong | High risk | Human-in-the-loop mandatory |
You don't always have to choose.
Consider a hybrid approach for a law firm scenario:
Situation: 40 staff law firm, lease agreement review taking 6 hours each Solution:
Total cost: $18,000 build + $200/month running Time saved: 4.5 hours per lease x 20 leases/month = 90 hours/month Annual value: ~$76,500
Payback: 3 months.
This approach doesn't build a "legal AI platform." It builds a specific tool for a specific problem using commodity AI as a foundation.
When someone asks "Should we build or buy?", our answer is usually: "Neither. Not yet."
First:
Then decide. This is exactly the kind of structured thinking we apply in our AI strategy consulting engagements.
Most problems don't need custom AI. They need a $99/month tool and a process change.
The ones that do need custom AI—those are where the competitive advantage lives. But only if you do it right.
We run a 2-hour Build vs Buy Assessment for $0. We'll audit your top 3 AI opportunities and tell you honestly which ones are worth pursuing and how.
No sales pitch. If a SaaS tool solves your problem, we'll tell you which one. Our AI strategy service helps businesses navigate these decisions with clarity.
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Solve8 helps Australian mid-market businesses implement AI that actually works. Based in Brisbane, working nationally. ABN: 84 615 983 732