Watch lookup fields reciprocally

Hi Formidable Community!

I'm a long-time Formidable user, and have done a number of projects using the plugin from the simple to the complex. I'm normally able to solve any of my Formidable issues by researching the documentation and support forms. However, I have a client request that I'm not able to solve (yet...hopefully).

Last year I built an inventory system using Formidable for an RV dealer. We have a view with a search form that uses some cascading lookup fields and some regular fields here: https://camptown-rv.com/current-inventory-all. This works well, but the client is not happy with the user experience. He wants a form more like this one on a competitor site: https://www.billplemmonsrv.com/rv-search.

So far I've created a truncated version of the new search form for testing here: http://55a.06d.myftpupload.com/test-search-page. Note that I've added some jQuery to submit the form each time a checkbox is toggled (I still need to hide the submit button). Also, the search parameters get passed in the URL but only the content inside the results container refreshes on submit.

The fields are all lookups, but none of them are currently set to watch. What I'd like to achieve, similar to the example, is having all of the lookup fields watch each other reciprocally. So no cascade. Rather, I'd like to start off with the form showing all of the options under each field (as if there was no watching set), and then limit/remove options as the user starts checking off boxes. For instance, if I were to check a manufacturer without checking a condition, category, or brand, I'd like the options in those three fields to have their options filtered as if they were "watching" the manufacturer field.

I don't think Formidable can do this out of the box. I've experimented with lookup and dynamic fields but I cannot get the behavior I'm after. I have pretty solid PHP skills and know a bit of javascript/jQuery, but I'm not sure exactly where to start with this kind of customization.

Has anyone ever created anything like this with Formidable? If so, I'd love to hear how you achieved it. I'm also open to contacts from developers who might be able to write the custom code for me.