How I evaluate a new vendor before placing an order

I get asked this constantly, so here's the actual checklist I use. It's not perfect, but it filters out ~90% of bad actors before I ever put a card down.

1. COA on file, batch-linked. Not a generic 'we test our products' page — an actual PDF tied to the batch number on the vial you'll receive. If the COA isn't dated within the last 12 months for that batch, that's a flag.

2. Independent lab, not in-house. The COA should name the testing lab and include their contact info. In-house COAs are not zero-value, but they're easy to fudge.

3. Refund policy that names specific failure modes. Vague 'satisfaction guarantee' language is marketing. 'Refund or replacement if lab purity is below X%' is a real policy.

4. Community history of at least 18 months. Brand-new vendors are not automatically bad, but a track record means problems would have surfaced by now. Search the community for the vendor name and read the criticisms, not just the praise.

5. Recent independent third-party test. Many vendor-agnostic testing services (e.g. Janoshik, MZ Biolabs) post results publicly. If a vendor I'm considering hasn't been tested independently in the last 6 months, I usually wait.

Optional but nice: clear shipping origin, responsive support email (test them before ordering with a simple question), and a domain that's been registered for more than a year.