Another idea (just testing it):

If you want to avoid setting up a Remote Server, why not just copy the
update-files into folders on any webspace and download it from there if
available? Quite easy to manage, I think.
Thus the "main"-database could be located on your office-computer
exchanging update-files with the clients.
At least for smaller projects that should work.

Any objections?

Uli

Forget about that; actually it's much easier to set up a server and to
use remote stores without any hassle.

Uli