Searching for 'not booked' in date range

I want to create a simple search which will return units that have not been booked in a given date range. An availability search but for 'General Availaibility', not 'Periodic Availibility', so in other words its simply booked or not booked on a given date, there is no blocked out or available/not available periods.

There doesnt seem to be any possibilty to perform such a search. I have read many posts and guides on search API, facets, views and for Drupal 8/9 it seems that this is simply not possible, even in a conceptual sense?

I have been able to create a view with some relationships that shows units not 'booked' on the date provided by the user, but this view also displays a unit as available because its booked on a different date, in other words, views is only good if you have one instance of each unit.

I've went down many different routes to try and solve this but I think the conceptual structure of the entities and relationships means this simply isnt possible in Drupal 8/9 without writing some fairly extensive custom code?

Am I missing something or does anyone have any tips on how to approach this?