Filtering Page Content Feature Boxes

My website is for a used car dealership, and while I should have gone with a pre-made car template, I often custom design styles and use Enfold 2017 to produce it. But I may have designed something over my head and am hoping you can help.

I’m essentially needing a basic search and filter function for my car listings (no other car listings plugins have worked).

I created an Inventory page that contains a list of “Page Content” content elements, each one being a new car listing that I created as a portfolio page. I did this because I want my portfolio entries to display one after the other as their full content, not merely images with a single title like the “Portfolio Grid” content element does or the the “Blog Posts” content element does. I’m open to working with posts but the “Page Content” feature does not display posts, only Pages and Portfolio.

And I really like how the “Page Content” content elements shows my full design of each portfolio car listing.

Here’s where I need assistance: I’d like to be able to filter these listings. Is it possible to have a filter read the content of each of the listings, in order to provide refined results? So if there was a car type drop down, you could then select from a list of cars that were being showed on the inventory page. I tried working with the Search & Filter Plugin, but that wasn’t working. The plugin is still activated if you want to work with it for a solution.

Here is a link to what I’m imagining (four searches for Year, Make, Model, and Color) and the drop downs of those searches would only contain info relating to the listing.
https://drive.google.com/file/d/1G2Zaej45ZteMVd_7cb_yqtv7oW8UZtea/view?usp=sharing

And here is a preview of what I’ve created:
https://drive.google.com/file/d/1tfuI-U8lsnKyArteO4v56VEwauxsxCyD/view?usp=sharing

If this is considered custom, I’d be happy to pay for the help!!