I've used one of the older Nests for a couple years in an Airbnb condo at Lake Tahoe to control the heat.  

Ductless heating works well here, but I'm worried about tenants breaking them.  

If there's just 6 right next to each other and you can get to the basement(s), it might be more feasible.If the current system is too complicated, might be worth considering to:Split out the electrical, upgrading service and adding min-splits for heating/cooling. 

I have a rental property about to go on the market and we have propane tanks and not sure how to structure the payment of this.  We will be providing the new tenant with full tanks because we are changing providers so...

He gave me a rough number. it does not include insurance and interest, so I plugged the insurance in the "other cost" excluding maintenance fees and vacancy.Estimated mortgage payments on 7/1 arm with 3 year prepay$2,182.00 excluding principle and Interest built into the loanMay need a personal loan of 30kRent a year$50,400.00 Monthly$4,200.00 A list of all Annual Expenses estimated run downWater/sewer/trash$2,200.00 Gas Heat$1,440.00 Common area Electric Annual$60.00 Insurance$2,920.00 City License 75.00 unit= 525 years$525.00 Management fee at 10%$6,000.00 County Tax$4,028.00 vacancyMaintenance feesThe other cost breakdownwater/sewer/trash bill$2,200.00 Gas Heat$1,440.00 Common area electric$60.00 City License$525.00 Total$4,225.00 not including maintenance fees

In the winter you will have to either heat it or winterize it which is going to cost you.Are you able to develop any of those 15ac to salvage the deal?

Features include a large living area with a heated and cooled attached sunroom.

From Zillow:Features include a large living area with a heated and cooled attached sunroom.

And there's usually enough heat from the other units to keep the pipes from freezing if one tenant shuts off the utilities.Lots of luck getting the tenant to pay any future judgement you get against her in small claims court. 

I don't live in Minnesnowta anymore, but putting in new windows and heating are a great upgrade.