Auto-linking (and summing) data across multiple boards without mirroring notes

I’ve been trying to crack this for a while now and have consistently come up empty. What I’m trying to do involves sharing data (some of it raw, some of it summed) across multiple boards that use different titles as items - but achieving this without having the notes/ updates made to the linked items copy over to one another.

The use case looks like this:

  • We have a deals board, with a connected (single direction) column to a companies board that is always filled in. Each deal has a value
  • I want to automatically pull a sum of the values for all deals associated with a specific company back to the company board, and list the value in a column
  • This can be achieved by setting up two way connection columns between the two boards, and then using a mirror column on the companies board to sum the associated value of all the related deals
  • However, doing this means that every update/ note/ activity logged to a deal is also recorded against the company, and vice versa - this is what I’m trying to avoid, as we tend to have 10+ deals per company and it will just mean both company and deal logs will become clogged with irrelevant updates

Any help would be hugely appreciated!