The maps know where every house is so the software simply has to route to those coordinates. We know it works because Google Maps and all the others I tried do

The maps know where every house is so the software simply has to route to those coordinates. We know it works because Google Maps and all the others I tried do it already. So all that is needed is to get the coordinates for each address, ask the api for the time between each possible pair of locations plug it in to your favourite travelling salesman solver and start driving. This is hardly a difficult task, especially as pretty much all of it is already done by various companies already. For instance https://www.mapquest.com/routeplanner https://www.mapquest.com/routeplanner. It only covers the US but it doesn't look as though there would be any difficulty extending it to other countries. And this one, https://planner.myrouteonline.com/route-planner/1752/# https://planner.myrouteonline.com/route-planner/1752/#, works perfectly in Hilgermissen and has no trouble finding the houses and finding the optimal route.