This sounds like something I wanted to do with my neighbor, but he has no interest in the building of models and electrical work (soldering, etc).
The way I though about running this with the best timing and syncing possible, based on my knowledge of networking, would have been to run a switch in a central spot between the houses to go to each of the controllers and one Ethernet cable to the computer running the show.
While I know WiFi is pretty good these days, I still don't care for the latency issues you can has. In timing with lights, 200ms can be noticeable, but I am also very picky. lol. Though, there are lots that use WiFi devices to avoid running too much cabling, especially with longer runs.
I'd be interested in what/how you achieved this, if you manage to get this going this year.
-Tim
