Hello to the community,
I am trying to build a Classifieds platform which would work little bit different.

In this scenario User would post a inquiry for things that he is looking for and the sellers would respond to this offering their.
Is something like this possible?

Thank you

You can use contact form as way sellers can contact listing owner.
Alternatives are using Instant messenger plugin or Make offer plugin.

Thank you very much.
Is there a offen extension

Make offer plugin:
https://osclasspoint.com/osclass-plugins/extra-fields-and-other/make-offer-plugin-i54

Thank you very much!
This is worth looking into it.

Welcome