I need to move 100's of documents from one SharePoint environment (2010) to another (2013). Is there a FREE gui tool to do this? I do not have direct access to server so PowerShell isn't an option at the moment.
Here you go! This should work fine! It also includes metadata
The Content Migration Wizard on CodePlex is a GUI tool and it is free, but you need to run it on the server. The GUI just generates the required PowerShell.
You could open both the 2010 and the 2013 libraries with Windows Explorer, then drag and drop. That's free, but the metadata won't be retained.
I doubt that there will be any free tools that do all you require and that can be used in the browser client without touching the server in some way.
If migration between environments is a business requirement, then get the people involved who DO have access to the server and run something like the Content Migration Wizard.