Ask a Klaviyo agency to show relevant evidence, explain who does the work and document what you retain if you leave. Check metric definitions and timeframes in case studies, then compare the proposal with the operating capacity your team needs.
On this page8 sections
- Start with proof appropriate to what confidentiality allows
- Ask about methodology, not just outcomes
- Get the pricing structure and its incentives in writing
- Check what happens if it doesn't work
- Confirm who actually does the work, and who owns your data
- A short vetting checklist
- Red flags that should end the conversation
- Use a real audit to test some of this directly
Start with proof appropriate to what confidentiality allows
Any agency can say they're good at Klaviyo. Ask for specifics: how many flows did they build for a comparable account, what was the measurable result, and what's the category, timeframe, and how the metric was defined and attributed. You don't need the client's name; many agencies anonymize results by default. Be suspicious of an agency that refuses to share any category-level detail at all, but don't require a name; that's a confidentiality norm, not a red flag on its own.
Ask about methodology, not just outcomes
A result without an explained method behind it is harder to evaluate, because you can't tell if it will repeat for your account. Ask specifically:
- Which flows do they build first, and why that order?
- How do they handle segmentation beyond the default Klaviyo templates?
- Do they test sends, and how do they decide what to test?
- How do they handle deliverability, especially around list hygiene and sender reputation?
An agency that can answer these in specific, technical terms has likely done this enough times to have a real system. One that answers only in generalities is harder to evaluate on process, which shifts more of your risk onto the outcome alone.
Get the pricing structure and its incentives in writing
Pricing usually falls into a flat project fee for flow builds, a flat or percentage-based monthly retainer for campaigns, or a mix. Hourly and advisory retainers exist too. Percentage-of-revenue pricing on campaign work rewards send volume; flat pricing removes that specific incentive but doesn't automatically guarantee better judgment. Ask directly what structure they use, why, and exactly what's included (strategy, copy, design, QA, reporting) versus billed separately (SMS, pop-ups, deliverability infrastructure).
Check what happens if it doesn't work
Ask what recourse you have if the first deliverable underperforms: is there a review window before you're locked into a longer commitment? What's the minimum contract length, and what's the stated reason for it? There's no universal "right" minimum. Ask the agency to explain theirs, and weigh whether the reasoning holds up for your situation specifically.
Confirm who actually does the work, and who owns your data
A common problem: you vet the founder or account lead, then the work goes to someone junior you never spoke to. Ask directly who will be writing copy, building flows, and reviewing QA on your account. Also confirm account ownership and data access: who holds admin rights to your Klaviyo account during the engagement, what happens to that access and to the flows/segments/templates built if you leave, and what the offboarding process looks like.
A short vetting checklist
| Question | What a strong answer sounds like |
|---|---|
| Can I see account-level results, appropriately anonymized? | Category, metric, timeframe, and how it was measured, even without a brand name |
| What's your flow-build order and why? | A specific sequence tied to customer lifecycle stage |
| How is pricing structured, and why that structure? | A named model (flat fee, flat retainer, percentage) with a stated reason |
| What happens if the first result is weak? | A defined review window before further commitment |
| Who does the actual work, and who owns the account setup? | A named person or team, plus a clear answer on data/access ownership |
Red flags that should end the conversation
- Refusing to share even category-level, anonymized detail about past results.
- Quoting a price before ever looking at your Klaviyo account.
- Pressure to sign a long-term contract with no review point and no explanation for the term length.
- No clear answer on who owns account access and what offboarding looks like.
Use a real audit to test some of this directly
An audit of your own account is one of the few parts of this checklist you can verify firsthand: what they find, how they explain it, and what they'd prioritize first tells you something a pitch deck can't. Book a free Klaviyo audit to see the methodology applied to your own data before deciding. For a sense of the category-level proof this checklist asks you to demand, see the case-study library published at hugewinmedia.com/email-case-studies.
Compare the proposal with published pricing examples and this rubric for reading case-study evidence.