Which plugin?

Any chance to elaborate what exactly you need to build beyond simple "supply and demand"? Screenshots, URLs, examples of existing apps?

We are a beekeepers association. Our members must be able to offer their materials for sale, but also place a question ad. Non-members are not allowed to place an advertisement, but they are allowed to view the supply and demand

Is there a plugin for this? Or can I get this from an example? Thanks

https://xlinesoft.com/phprunner/docs/classified_template.htm
Live-Demo : https://xlinesoft.com/livedemo/business/classified/clmain_list.php

In my opinion, the "Classified Ads Template" is coming nearest to the requirements,
with minimum efforts to be made to "customize" in regard to "question ad".

https://xlinesoft.com/livedemo/business/classified/clreply_add.php

Say, simply to ADD missing further vital fields into the feedback form is quickly done and
simple even too.

Thanks for the useful information. I'm going to check it out

The lack of any relevant info in this post terrifies me. I'm pretty sure that "they are allowed to view the supply and demand" tells a kot to someone who is in the beekeping business but for us, mere humans, it doesn't tell much.