Getting Support from Agent Evolution

Hi, I’d like to list on each listing the listing agent (using get_author hook) as well as some other author meta, and a query for other listings by the same agent.

Before I dive into writing this code, though, I wanted to ask:

-Is there already some code written for this? And if not, then:
-What’s the best course of implementation as to not interfere with plugin’s core function codes? Ideally, I want to add this somewhere that won’t be overwritten by future updates.

Thanks! Tom