Help Dreamweaver Experts, I'm trying upload files to local host upon saving in DW

After re-reading your question, I realize now you're talking about local server, not remote.  Sorry about that.

Simply move your local site folder into your testing server's default web directory.   See my screenshot below.  On Wamp server, it's the www folder.  On Xampp or Mamp, it's the htdocs folder.    With this set-up, there is no need for duplicate files or pushing files to local server.   It's one less thing to think about.  

Uploading files to remote server on save is dangerouse.  You could accidentially bring down your whole site with one mistake.  It's not worth the risks.  Always test your site locally before you upload to ensure everything is working correctly.  

If your online site isn't updating, try these steps first:

1. Refresh your browser with Ctrl+R.  Or clear the cache memory through browser tools/options.
2. Check to ensure you're uploading to the proper root directory.  See screenshot.
   
3. Make sure you're uploading to the correct server.
4. Failing all of the above, contact your hosting provider to find out if they are caching on their end.