Documents management has been very important for every organization for the process and handling of various important documents for travel, employees, financial, expenses etc. So there is a very important need of a good document management system which is cost efficient and also easy to use so here I am listing out some of the open source document management systems which can fit in your needs and save a big cost to your company too.
I personally prefer openKM which is one of the best document management system which allows businesses to control the production, storage, management and distribution of electronic documents, yielding greater effectiveness and the ability to reuse information and to control the flow of the documents. More details https://www.openkm.com/.
I am also a big fan of alfresco which has it’s own both enterprise and open source community versions as per your needs and it is one of the best in support when you go for commercial enterprise licenses making it at par with other document management system. More details http://www.alfresco.com/.
Another one of the good DMS is LogicalDoc where documents can be organized into hierarchical folders, searched using the integrated search engine, or browsed by Tag.The application is implemented as a plugin system that allows users to add new features. More details http://www.logicaldoc.com/en/.
One of the DMS which is based on php is opendocman which is quite easy to setup and use with a very friendly user interface including auto-updates, revision tracking etc. More details on http://www.opendocman.com/.
There might be others too but which I have not covered personally because I haven’t used them in my career so please feel free to explore at your end but I tried to get the best ones for you.
Feel free for any comments or queries.