Efficiently Combining Data from Apollo, Zoominfo, and Clay People Finder

Could someone give me the most efficient way to combine three sources of data. I want to import from apollo, Zoominfo, and and of course clay people finder. My concern is that if I do a dedupe Clay may keep the first data(Name) but not allow it to be updated with a phone or email that may come from another source. Can I do it in clay or is it best to import each source into clay then export/update Google Sheet