A fast first step is to look for platforms that publish clear marketplace stats (number of offers, companies, and categories) and provide transparent support/contact details, because that usually correlates with better accountability.

On https://arico-b2b.com/de, for example, you can immediately see high-level figures like product offers and company counts, plus a broad category structure that helps you sanity-check whether suppliers in your niche are actually active.

Then, open a few listings and verify consistency across the company profile, product descriptions, and any legal pages (imprint/terms/privacy), since mismatches are an early red flag.

Finally, I’d shortlist suppliers who provide complete company info and respond through official channels, and ignore listings that feel anonymous or unusually vague.