So the best way to combine Apollo, ZoomInfo, and Clay People Finder without losing important info is to import them separately into Clay first. Don’t dedupe right away use the “Find existing row” step to match contacts by email or LinkedIn. That lets you update missing fields (like pulling a phone number and Personal emails from ZoomInfo or from Searchleads paired with Apollo) without overwriting names or titles.
Once you’ve merged everything and filled the gaps, you can either keep it all inside Clay or export the clean list to Sheets. Clay’s way better for managing this though just gotta set it up right! Let me know if you want help setting it up!