What's the most cost-effective way to debug onboarding and checkout issues using session replay software?

The most cost-effective approach is usually not to turn on full session replay for everyone. Instead, use a targeted, event-driven setup:

Best-practice low-cost setup

1. Capture only critical funnels

   • Onboarding
   • Checkout
   • Payment failures
   • Signup/login

2. Replay only sessions with signals of trouble Trigger replay collection when users:

   • abandon checkout
   • hit validation errors
   • loop on the same step
   • encounter API/JS errors
   • rage click or dead click
   • spend unusually long on a step

3. Sample aggressively

   • 1–5% of normal traffic
   • 100% of sessions with errors or failed conversions
   • Higher sampling only on the pages you care about

4. Mask sensitive data

   • credit card fields
   • passwords
   • emails if needed
   • reduce compliance overhead and risk

5. Use short retention

   • Keep replays for 7–14 days unless you need longer
   • Most debugging happens soon after the issue is reported

What makes this cost-effective

• Lower storage and bandwidth usage
• Fewer recordings to review
• Faster root-cause analysis because you focus on failure cases
• Lower privacy/compliance burden

Ideal workflow

• Instrument key events in the funnel
• Set rules to record only problematic sessions
• Correlate replays with console errors, network failures, and backend logs
• Review a small set of high-signal replays daily/weekly

If you want the cheapest workable version

A very lean setup is:

• record only onboarding and checkout pages
• sample 1–2% of all sessions
• always record sessions with errors or checkout abandonment
• mask all sensitive fields
• keep 7-day retention

In short

The most cost-effective strategy is targeted replay + error-based capture + aggressive sampling.
That gives you the debugging value of session replay without paying to store and inspect every session.

If you want, I can also suggest a specific ruleset for tools like FullStory, Hotjar, LogRocket, or PostHog.