The perfect solution to your problem would have been Microsoft Streets and Trips 2013 but MS discontinued it in 2014(?).
If you are in Europe there was Microsoft Autoroute 2013.
The 14 day demo versions are still available on the MS web site. https://www.microsoft.com/streets/en-us/free-trial.aspx https://www.microsoft.com/en-gb/autoroute/free-trial.aspx
If you run the demo in a virtual PC (say Win XP in VBox) that you discard every 14 days you can run it forever.
As an individual I would have no ethical concerns about doing this because the program is no longer sold by MS so I wouldn't be depriving them of any income (I have a licenced copy so it's not an issue) but as a business you would have to check whether this is legal and ethical for you.
There was another MS program for business called MapPoint that was S&T on steroids.
There is a text tutorial for MapPoint on the following website: http://www.mapping-tools.com/howto/mappoint/introduction/
They used to have an excellent video tutorial on MapPoint. I've had a quick look around the web site but I couldn't find it. If you contact the very friendly owner of the web site he may provide you with a link if it is still available.
I haven't looked at the text tutorial but the video tutorial covered the route planning situation you have described.
Since MapPoint was discontinued Mapping Tools has pivoted to support another mapping product that MAY do what you want to do. Have a look around the web site or contact them to see if they can help you.
If you do decide to go down the S&T route (pun intended) it would allow you to import your addresses from your spreadsheet and then optimise the route to minimise the time taken to visit all sites. S&T would also allow you to manually re-order the sites or re-route to avoid known route problems (eg don't try and turn left at a particular intersection on a busy road because there aren't any traffic lights) by clicking and dragging the route.
Once you have decided on the optimum route you can export it as a GPX file and then import it into say a dashboard satnav personal navigation device (PND) or an Android tablet. I have no experience with what device or Android app would be suitable for doing this. Hopefully, someone else on this site can provide you with suggestions / recommendations.