The location is semi rural, my bank has branches in the next 2 biggest towns with limited hours, however there is a Walmart there as well.

I’m a semi-green investor looking to get started on my first deal.

As long as you are willing to be at least a semi-active investor after you retire. 

It should cash flow around $500/month... using semi conservative assumptions.

When I semi-retiree from my corporate job in two years I may look into retaking the classes and getting my license then since I might have time to play the retail side of things. 

You'll have no shortage of people who are interested in it at that price range(50/night = 1500/mo for a bed, 70/night = 2100/mo), and that puts you at around 5-6k/mo with 100% occupancy, and since your rates are semi-competitive with long term rentals but you're offering more value(furnished, short term), you shouldn't have much trouble reaching those numbers.

Around here (semi rural DFW TX) small multis (4-8 units) are going for about the same or a bit more per unit as a nice doublewide on an acre of land. 

I'm up in NH but it's good to meet (semi) local people that are getting into investing!

Once you move out of SE MI: how and by whom will this 14 unit building be managed?

In addition to draining the tank {semi-}annually to remove buildup, you will still need to have the gas side of your heater serviced every 1-2 years (just as you would have been doing with the old ones and your furnaces/boilers).