Xero and Hubspot integration - API or Zapier?


I’d like to be able to update Hubspot with billing amounts from our Xero system. I’ve tried to setup a Zapier zap but it’s clunky (in that it updates to individual contacts rather than to companies - which is daft, since it’s companies that you bill…) Anyway - I would be very grateful for advice on ways to do this better? I’ve read somewhere that others have had more luck integrating these two - so would be grateful for advice!