Hi Zoho CRM Team!

I try to implement access control matrix to Potentials and don't now exactly how to do this.
We have 2 groups: sales representative and product managers.
One Product Manager is responsible for brand "One" and should have a visability (read only) to all potentials regard to this brand for all sales reps, second PM is responsible for brand "Two" and should have a visability to all potentials regard to this brand for all sales reps. The PMs should be able to see potentials conected only to their brands.

The brand can be set as an additional filed in potential form.

Thank you for any sugestion, solution
Marcin