How do I use 'Make' or 'Zapier' for calculated properties?

[AExterna]

I have a free plan and needed a calculated property (in deals), but since it's not available on that plan, I was advised to use Make or Zapier. I've tried, but I couldn't get Make to automate all the properties, and the examples it generated only increased the value of one property. I just wanted to subtract between properties and calculate a percentage of a property, and of those calculations, only one property was a HubSpot property.
Is there anyone who can help me get this integration working? I'm a complete beginner with very little programming knowledge (almost none).

[MichaelMa · Accepted solution]

In Zapier, you can have it trigger on an event like a Deal Property change. Zapier's AI zap generator is can actually do most of this for you, if you know how you want to do.

Zapier Prompt: In HubSpot, when a Deal is updated, update the HubSpot field "changed_value" with the difference of between the HubSpot fields "last_year_value" and "this_year_value".

Generates this Zap:

You would just have to set up all the connections (eg, Object ID retrieved from the 1st action).