Module for accounting and preparation of documents, archiving

Good day!
I represent the interests of the human rights public non-profit organization from Ukraine “Law and Justice”.
Our main activity is representing the legitimate interests of members of the organization, which were violated by the illegal actions of officials and security officials.

We really liked ERPNext, and we are trying to use this system to make our work more efficient.

However, they came across the fact that ERPNext does not have a module for accounting and preparation of documents, archiving.

Perhaps such an application was created by someone for their own needs.

Thank in advance!

Do you have a solution for document management?
In addition, I am interested in a solution to integrate communication using social networks.

How can you get it, and how much does it cost?