QUICK ANSWER

Run both. Keepa Product Finder filters the entire UK Amazon catalogue to surface candidate ASINs; SellerAmp SAS validates each candidate at the supplier-page step. They aren't substitutes — they're sequential. Total cost ~£30/month and this is the standard UK OA tool stack. If you can only afford one: Keepa first (€19/month, includes Product Finder + chart data), then add SAS at month two.

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The two stages of OA sourcing

Online Arbitrage breaks into two stages every UK OA operator runs:

  1. Sourcing. Find ASINs that look promising — sufficient sales velocity, stable buy-box, not gated to me, not IP-risky.
  2. Validation. For a specific deal (this ASIN, this supplier, this price, today), confirm the unit economics work — ROI after fees, after VAT, after expected return rate, with sufficient cashback breakeven margin.

Keepa Product Finder serves stage 1. SellerAmp SAS serves stage 2.

What Keepa Product Finder does

Filter the UK Amazon catalogue by criteria like:

Output: a list of 30-200 candidate ASINs. None of them are validated yet; you don't even have a supplier link. This is sourcing.

What SellerAmp SAS does

You're now on a supplier page (Tesco, Argos, B&M, a brand's own site). The product matches one of your Keepa-found ASINs. SAS opens an overlay showing:

Output: yes/no decision on this specific buy. This is validation.

Why running both is the standard

Sourcing and validation are different problems requiring different data.

The stack is ~£16/month (Keepa Premium) + ~£15/month (SAS) = ~£31/month total. This is the standard UK OA toolkit and it pays back in the first 1-2 buys of any month.

If you can only afford one

Keepa first. Reasons:

The verdict

Run both. They're not substitutes. Keepa Premium for sourcing + SellerAmp SAS for validation = the standard UK FBA OA tool stack at ~£31/month total. If budget-locked to one, start with Keepa, add SAS within 60 days.

FAQ

Are Keepa Product Finder and SellerAmp SAS the same thing?

No. Keepa Product Finder is a catalogue search tool (find candidate ASINs across all of UK Amazon). SellerAmp SAS is a per-deal validator (evaluate one supplier-to-Amazon match for ROI and risk). They're stacked, not substitutes.

Can I do UK OA with just Keepa Product Finder?

Partially — you'd source candidates with Keepa and validate manually using its chart data. This works for ~30 deals/week solo but is slow. Adding SAS at £15/month roughly triples per-hour validation throughput.

Can I do UK OA with just SellerAmp SAS?

Only if your sourcing comes from somewhere else — paid lead services like Source2Store, free UK OA Discord channels, or supplier price lists you already have. SAS validates; it doesn't source.

Should I get SellerAmp or Keepa first as a beginner?

Keepa first. The chart-reading skill is foundational, and Keepa Product Finder gives you sourcing capability. Add SellerAmp in month 2 once you're validating 10+ deals/week and the manual ROI math is eating time.

How much is the standard UK OA tool stack?

Keepa Premium (~£16/mo or €149/yr) + SellerAmp SAS (~£15/mo or ~£135/yr) = ~£31/month or ~£284/year. Add SellerBoard for profit tracking (~£15/mo) and you're at ~£46/mo. That's the lean UK FBA OA stack.

Does SellerAmp work without Keepa?

Technically yes — SAS has fallback data sources. In practice, SAS is materially less accurate without an active Keepa Premium subscription underneath because BSR history and monthly-sold figures lose depth. Run both.


Educational content from a live UK Amazon FBA operator. Not financial, legal, or tax advice — talk to a qualified UK accountant for your specifics. Tool features and prices change; check the vendor's site before subscribing.

Related from the Method FBA blog: Keepa for UK FBA — chart-reading tutorial · A2A arbitrage UK · £5K Amazon FBA UK playbook · All recommended tools.