Complex bulletin board

I have a question: how to properly implement a complex bulletin board.
Suppose we have a real estate category, I create a content type "real estate," fill in the fields, and save it. But what if within real estate I have a subcategory with different fields? Let's take an example where I have "apartments" and "houses." Should I create two content types or just one "real estate" content type that includes all fields (I found this approach on another forum)? What about taxonomy in this case? I am a web developer with extensive experience (7 years) and have just started working with Drupal 8 since it is widely promoted; before that, I wrote my own projects on frameworks.
Ideally, this is how I see the solution to my problem but don’t know how to implement it in Drupal:

Content type 1 – Listings
We add taxonomy with all categories; each category has its own set of fields, and when adding a listing and selecting its category (taxonomy), the fields related to that taxonomy should appear.

So far, I understand that I will have to create a taxonomy for listing categories and add a separate content type for each category, but how to link this all when adding a new listing on the site? The user will have to select both the content type and taxonomy (category), which is confusing.

What should I do for a complex bulletin board implementation?
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