Group by a value in a referenced Collection

Hey everyone

Here is my link
https://preview.webflow.com/preview/sentinel-homes?utm_source=sentinel-homes&preview=93617cf37bbbf6e6db216eae8a62f4c3

Looking at the ‘House & Land Packages’ static page.

I want to show all the house & land packages from the collection in the CMS, but grouped by geographic location.

The geo location is only present in the collection ‘Listing Agents’ which is linked to House & Land Packages collection via a reference field.

Any ideas here?
I tried just manually putting a filter in 'where listing agent =" but that only lets me add one agent. There are multiple agents in each location.

Another restraint… I am filling the House & Land packages collection from an external source via the API, so cannot add any data / fields to that.

Any ideas appreciated.

Thanks!


Here is my public share link: LINK
(how to access public share link)